Installing a 454 in my 71 4x4

[71blksuper4x4]

I know you guys have heard and answered this question before, but what are the procedures for dropping in a big block in my 71 swb 4x4? I know one idea is to put a 2-3 inch body lift, but I already have it lifted 5 1/2 sus. so I didn't want to do that. I have also heard that you can take a 73 crossmember and scoot it up on the frame, and take 73 big block mounts and somehow fit those in to keep from notching the firewall. I really do not want to cut the firewall on a cheyenne super, so if anyone out there can get me some tips, I would sure appreciate it. (I have already found the 73 components, just need to hear if it will work or not)