68 GMC SB Big block swap

[78classic]

Spent a little time searching this forum and I think I am more confused about what I need than Before? Can someone with experience help me out. Have a 68 GMC SB 1/2 ton 2WD 6cyl 3 on tree. I just bought a 85 3/4 ton 454 Turbo 400 2wd for a donor.

From what I can tell all I need to do is use the 85 big block perches that will bolt to same holes in my 68 and lay it in there. Could I use the cross member off the 85 with out to much work? What about exhaust? will the stock manifolds fit? I already have the auto column \ Linkage I pulled from a 68 auto truck.

Any help appreciated this has been a 10 year project and finally getting it out of the paint shop to get the drive train in and get it on the road.