Thanks for the info!
The reason I'm trying to pull this off is simple.
My goals for this truck are to make a driver which includes dropping in a small block, appropriate tranny, driveshaft, rear end ect...
This 77 frame can be had for next to nothing. The rear end looks to line up well and I get almost everything I need in a tidy package. It would save me a lot of money in parts if can work. My fabricator seems confident that he wouldn't have a problem making the changes needed to mount my truck on it. I was just hoping to find some more info to make me feel more at ease with the idea.