Alright, if you don't mind, here's exactly what I did.
I patched the exe, now my forza shows up as Non-XBL Forza Motorsport on the game list, and the new save folder is working. I made a brand new saved game to check it out.
I unzipped the save file, and I put the UserProfile.xml file into the temp folder is the save resigner, and I opened up the save resigner, chose forza motorsport and then I chose the UserProfile.xml file and hit apply. Then I copied the userprofile back to the save file folder, and I FTPed the folder directly onto my xbox without using the save manager (because when I made a zip out of the folder, xbox manager still didn't find it for some reason) and when I went into the game, it was on the profile list, but it said damaged.
Did I miss something? P.S. The resign info I used was [4D53006E]
ID=[4D53006E]
Title=Forza Motorsport
SigKey=DD46A68DB08C6B0086FDE4F198E0C656
AuthKey=31A43F9B548DB278EF1D0AF8E74BD5B016324526
DataFile=UserProfile.xml
SigOffset=-20
DataOffset=0
DataLen=-20
SigType=NoRoam