All good advice above. If you can get your frame and body as a package deal already fit together, do it. However..,

In my case I didn't have the cash on hand to do that all at once, so I got my frame first and have built the rolling chassis and driveline. I just recently ordered my body and hope to have it in a couple of weeks. The thing to watch for is good quality. I got my frame from a shop in Ormond Beach, Florida (Clarke Hot Rods). They use frame rails from Shadow Rods which are supposed to be some of the good ones. My body (Bebops) is coming from Fat Cat Rods in Georgia which also has a good reputation. If both of these components conform to stock '32 configuration as they should, they should fit together with no major hassles. If there is a problem, I have extensive experience with both steel and fiberglass, so it's on me to fix it. If you're interested you can follow my build here on Club Hotrod.