6cyl tranny crossmember location vs 8cyl

[grancuda]

I have a factory '72 GMC LWB 6cyl man 3 speed on the column that I am swapping the motor. I bought a factory '71 GMC LWB 350 w/3 speed manual that has a hurst Indy shifter. The '71 has a 40k mile GM 260hp crate motor, new exaust, HD Radiator(on SPID) but the truck is in sad shape vs my low mileage '72.

I am planning on swapping the motor, radiator, exhaust system, rear leaf springs, and then moving the '71 with the 6 cyl.

Can I mount the 250 6cyl in the front position and run an electric fan? Can the z bar work on the 6 cyl in this position?
Should I remove the rivets holding the transmission cross member? What would that do to the floor shifter, move it back?
Could I swap out the front drive shafts to make up the difference in themounting position?

I would really prefer to leave the cross member where it is and just put the 6 cyl in the forward position on the one that is going.