Yes the early 5.7 did have head issues when over heated and dropped valves if the block is good just get a set if eagle heads for it. And drop it in your Abody. Well maybe not drop it in more like cram shift pull it out again put back in move pull out put in.............repeat
I have lots of fabrication tools! Probably look more like an early Nascar horseshoe front subframe when finished. Definitely not enough room to get it in between the inner fenders on a first Gen A-body.