1990 c1500 lq4 6.0l swap

well hello all im new to this forum i have been jumping from different forum doing alot of reading as im putting a 6.0ls into m 1990 chevy c1500. a few questions i have is......
im putting the 4l80 in with is i have read some guys are successful with no trans crossmember and some havent anyone chime on this
also driveshaft i know there is a spline difference between the 2 shafts (700r4 to 4l80) can a guy get different sized cups for a u joint to accommodate the 2 different yokes and is a guy looking at a different length of shaft. thanks alot.