Auto to 4-Speed Swap
Yes, crossmembers are the same.
Driveshaft should be the right length, but when I did my swap I also got the driveshaft from the donor car cause the 4speed has a larger output shaft and the yoke for it takes the larger u-joint. I had to use the driveshaft and yoke from the 4speed car, and used a conversion u-joint at the back to connect to my 8-3/4 which took the smaller u-joint.
Just some things to think about.