" Also what is the average cost of getting the drive shaft cut down?"
Depends on where you are. I paid $130 to have the drive shaft shortened, balanced, new U joints front and rear. They even painted it !
I've seen folks in other parts of the country pay in the $200 neighborhood though.
If that crossmember you are talking about has e-brake stuff on it , THAT Won't work !!
Also, I don't think you NEED a crossmember for the 4 speed trans, just bolt it to the bell housing and that's all that's needed. Automatics require a rear support, or 5 and 6 speed manuals, but not 3 and 4 speeds.
Val