Do the back seats fold down and give trunk access in these old sedans and coupes? If so, do they split, or does the whole seat back come down?

Thanks

No, but GL-10 coupes (and probably sedans too) had a fold-down rear center arm rest.

Yeah , snag a GL-10 rear seats if possible.

You can fit 8’ lengths and even a ladder that way. Yeah I know you’re not going to do any of that , but just stating some fact.

There’s also a cover channel that goes over the rim of the pass through hole so you don’t rip stuff or scrape your hands. Anyways , you’ll see if you ever get the opportunity. I’ve done this swap on ea81,EA82, and now have done it with our 92 Legacy Sedan.