To me the decision to leave the body on the frame or remove it is the first big decision. From there I would say that removing the engine is a must and makes it a lot easier to deal with what is left ( body and frame are lot lighter to move around and you will need to remove it eventually). I am in the process of a body off and have done two body on restorations. The decision to leave the body on to me was dictated by the condition of the body (rusty panels) especially the floor panels. I guess that your goal of how complete the restoration should be also dictates if the body comes off the frame. The body does not have to come off of the frame to have a concours car so don't let that drive your decision. My first "body on" is a two time VTR Concours First Place and the second is a People's Choice winner.
I am rebuilding the front suspension first on the body off restoration. It just seems like a good place to start. Oh yes one thing that I did was to remove things off of the car and put them in sealable sandwhich bags with a note of what they are or where they came from. This has proven to be most helpful for projects that last for a year of more. Geting the correct size,length and grade of bolts has been most helpful in putting it back together. You can swap out for newer bolts if needed, but at least you have the old one to look at.
If you mave more specific questions please ask.
Charley Fitch
