swapping a 700r4 to 4l80e

[jeffmarble]

maybe im not searching right but i couldnt find much info on swapping a 700r4 to a 4l80e. i found a great deal on a drivetrain combo via craigslist 383 with edelbrock multi fuel injection and serpentine setup. 4l80e and np241. will i need to lengthen or shorten driveshafts? and crossmember location will it stay the same? will anything change with the transfer case ive read there about the same. anything else will be a great help thanks. oh heres the link of what im gauging interest in.http://anchorage.craigslist.org/pts/2099452440.html