First try

main.py

-import requests, time, re, os, configparser, sys, argparse
+import requests, time, re, os, configparser, sys, argparse, shutil
 from bs4 import BeautifulSoup
-from PIL import Image
-from io import BytesIO
-
-css_to_change = ["https://www.somethingawful.com/css/main.css?12",
-                 "https://forums.somethingawful.com/css/bbcode.css?1456974408",
-                 "https://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/themes/redmond/jquery-ui.min.css",
-                 "https://www.somethingawful.com/css/globalmenu.css",
-                 "https://www.somethingawful.com/css/forums.css?1545838155"
-                ]
-css_to_change_to = ["main.css",
-                    "bbcode.css",
-                    "jquery-ui.min.css",
-                    "globalmenu.css",
-                    "forums.css"
-                   ]
-
-scripts_to_change = ["https://ajax.googleapis.com/ajax/libs/jquery/2.2.2/jquery.min.js",
-                     "https://cdnjs.cloudflare.com/ajax/libs/jquery-migrate/1.4.0/jquery-migrate.min.js",
-                     "https://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/jquery-ui.min.js",
-                     "https://forums.somethingawful.com/js/vb/forums.combined.js?1476414227",
-                     "https://twemoji.maxcdn.com/2/twemoji.min.js",
-                    ]
-scripts_to_change_to = ["jquery.min.js",
-                        "jquery-migrate.min.js",
-                        "jquery-ui.min.js",
-                        "forums-combined.js",
-                        "twemoji.min.js"
-                       ]
-
 
 def main(args):
-  print(f"Fetching from thread {args.thread}.")
-  if not os.path.isdir("archive"):
+  print(f"Fetching PDFs.")
+  if not os.path.isdir("pdfs"):
     print("First-time setup...")
-    os.mkdir("archive")
-  if not os.path.isdir("archive/css"):
-    print("Setting up CSS...")
-    os.mkdir("archive/css")
-    for f in range(len(css_to_change)):
-      r = requests.get(css_to_change[f])
-      with open(f"archive/css/{css_to_change_to[f]}", "w+") as file:
-        file.write(r.text)
-  if not os.path.isdir("archive/scripts"):
-    print("Setting up scripts...")
-    os.mkdir("archive/scripts")
-    for f in range(len(scripts_to_change)):
-      r = requests.get(scripts_to_change[f])
-      with open(f"archive/scripts/{scripts_to_change_to[f]}", "w+") as file:
-        file.write(r.text)
+    os.mkdir("pdfs")
     
-  if not os.path.isdir(f"archive/{args.thread}"):
-    print(f"Creating directory for {args.thread}...")
-    os.mkdir(f"archive/{args.thread}")
-  if not os.path.isdir(f"archive/{args.thread}/images"):
-    print(f"Creating directory for {args.thread}/images...")  
-    os.mkdir(f"archive/{args.thread}/images")
   config = configparser.ConfigParser(interpolation=None)
   if not os.path.isfile('config.ini'):
     print("config.ini is missing!")
     print("username and password must be present in config.ini.")
     sys.exit(0)
 
+  INFOVAYA_ROOT = "https://events.infovaya.com/"
+
   info = { "username": config["DEFAULT"]["username"],
           "password": config["DEFAULT"]["password"],
           "action": "login"
           }
 
   s = requests.Session()
-  q = s.post("https://forums.somethingawful.com/account.php", data=info)
-
-  if f"lastpage{args.thread}" in config["DEFAULT"] and config["DEFAULT"][f"lastpage{args.thread}"] != "":
-    lastpage = int(config["DEFAULT"][f"lastpage{args.thread}"])
-  else:
-    lastpage = 1
-
-  i = lastpage
-  parse_ok = True
-  while True:
+  q = s.post("{}login".format(INFOVAYA_ROOT), data=info)
+  q.raise_for_status()
+
+  sessions_request = s.get("{}event?id=88&actionMenu=sessions".format(INFOVAYA_ROOT))
+  sessions_request.raise_for_status()
+  sessions_page_soup = BeautifulSoup(sessions_request.text, "html.parser")
+  print("Starting to search for PDFs. This may take a while...")
+  for session_link in sessions_page_soup.find_all("a", href=re.compile("session\?id")):
     time.sleep(0.05)
-    payload = {'threadid': args.thread, 'pagenumber': str(i)}
-    r = s.get("https://forums.somethingawful.com/showthread.php", params=payload)
-    if "Specified thread was not found in the live forums." in r.text:
-      print("That thread does not exist or is not accessible to you.")
-      parse_ok = False
-      break
-    if "The page number you requested" in r.text:
-      i -= 1
-      break
-    print(f"Fetching page {i} in thread {args.thread}.")
-    with open(f"archive/{args.thread}/page{i}.html", "w+", encoding="utf-8") as file:
-      soup = BeautifulSoup(r.text, "html.parser")
-      for tag in soup.find_all("link",{"href":True}):
-        if tag["href"] in css_to_change:
-          tag["href"] = "../css/" + css_to_change_to[css_to_change.index(tag["href"])]
-      for tag in soup.find_all("script",{"src":True}):
-        if tag["src"] in scripts_to_change:
-          tag["src"] = "../scripts/" + scripts_to_change_to[scripts_to_change.index(tag["src"])]
-      for tag in soup.find_all("a",{"title":True}):
-        if tag["title"] == "Next page":
-          tag["href"] = f"page{i+1}.html"
-        if tag["title"] == "Previous page":
-          tag["href"] = f"page{i-1}.html"
-      if args.images:
-        for tag in soup.find_all("img",{"src":True}):
-          src = tag["src"]
-          if src[:4] != "http":
-            src = "https:" + src
-          imgname = src.split("/")[-1]
-          fullpath = f"archive/{args.thread}/images/{imgname}"
-          if os.path.isfile(fullpath):
-            tag["src"] = f"images/{imgname}"
-          else:
-            img = s.get(src, stream=True)
-            if img.status_code == 200:
-              try:
-                theimage = Image.open(BytesIO(img.content))
-                print(f"\tSaving {fullpath}.")
-                theimage.save(fullpath)
-                tag["src"] = f"images/{imgname}"
-              except:
-                print(f"\tImage {src} not available.")
-            else:
-              print(f"\tImage {src} not available.")
-      file.write(soup.prettify())
-    i += 1
-
+    page_request = s.get("{}{}".format(INFOVAYA_ROOT, session_link["href"]))
+    page_request.raise_for_status()
+    page_soup = BeautifulSoup(page_request.text, "html.parser")
+    page_title = page.soup.h1.string
+    for pdf_tag in page_soup.find_all("a", href=re.compile("pdfviewer")):
+      pdf_name = pdf_tag["href"].split("/")[-1]
+      file_name = "{}-{}".format(page_title.replace(" ", "_"), pdf_name)
+      pdf_request = s.get("{}{}".format(INFOVAYA_ROOT, pdf_tag["href"]), stream=True)
+      pdf_request.raise_for_status()
+      print("Fetching PDF for '{}'...".format(page_title))
+        with open(file_name, "wb") as file:
+          pdf_request.raw.decode_content = True
+          shutil.copyfileobj(pdf_request.raw, file)
+          print("Saved as pdfs/{}".format(file_name))
+  
   print("Finished fetching thread.")
 
-  config["DEFAULT"][f"lastpage{args.thread}"] = str(i)
-  with open("config.ini", "w") as file:
-    config.write(file)
-
 if __name__ == "__main__":
   parser = argparse.ArgumentParser()
   parser.add_argument("thread", action="store", help="The threadid from the thread's URL")