May need engine crossmember and towers for big block

[Yukon Jack]

I'm swapping a big block into my 69 4x4. The 67-72 4x4's didn't come with big blocks and I've heard one solution that provides better header fitment is to use an engine crossmember and towers from a 73-87 truck.

I assume the 73-87 setup is different depending of if it is a big block or small block but I don't know if that is correct.

In the event I decide this is the better approach, does anyone have these parts and if so, what is your asking price?

[Desert Rat]

Yukon as far as ive heard from people that put BBC in there 73 up 4x4s you just simply blt them in,unlike the 67 ups you can use your existing parts but need to move it all foward for firewall clearance or ive seen some people use a BFH to massage firewall for clearance(not my preferred method)but if you move motor foward be ok,but then you will have to mess with driveline and etc.Im not sure on the 73 up mounts fitting on a 4x4.i have 73 up 2wd mounts from 454 trucks but i dont see any visual difference of those out of my originally equipped small block 2wd Blazer,i used the stock small block mounts in it,and it fit perfect,the 73 towers i have 1 set from SWB 73 454 truck i parted other set from 454 3/4 ton,noticed 1 set in longer.if you have a welder and good at doing some fabrications id say go with what you have.Theres some Big Block 4x4 trucks 73 up style in in boneyards here that i got the motors from,i can see what the difference is if any,maybe SB and BB in those years were sam as in 2wd?sorry i wasnt alot of help.I know the 73 2wd x members fit,ive bolted them in with minor mods,ovaling a couple bolt holes but im not a 4x4 guy.have you tried coloradok5.com thats alot of 4x4 action there!