Are they pretty much the exact same for each side? I've got my motor so far back and up that that the truck manifolds exit right into the lip seal on the firewall in the YJ.
....i put a 5.3 in my jeep and i had to trim the lip (where the floor and upper part of the tub meet) about down to nothing and the manifolds are still very close. on these vette manifolds i tried them and said the hell with it, they were dumping too low where my upper 4 link bars are mounted.