5.7 swap questions?

just recently i almost bought a 64 plymouth fury 2door hard top and a 65 dodge dart. its kinda funny. they two same body styles i like and there are two guys on here doing the build i want to. the deal on the 5.7 i had going fell through. now i gotta try to find a new motor. i want used. what are the main differences between the 6.1 and the 5.7? i know the heads are interchangable, the blocks are the same, 6.1 heads require a 6.1 intake. bores are a little different. but would it be a bad idea to snag a 6.1 if i can? im really ticked off about the motor deal. but you know, sh*t happens.