Yes they can be swapped over, but it mIGHT give soem harsh 2-1 downshifts as well as harsh engagements goign from nuetral to in gear. GM used a proprietary C5 apply piston design that was smaller than other 1000/2000 series transmissions. The C5 piston is part of the tailhousing, so when you swap it you must also swap it as well if you do this style swap. You also MUST be careful when doing it to verifu proper endplay, and to do it with the trans standing up on the bellhousing so as to avoid dropping a torrington bearing out of place. I'm pretty sure that the 2 wheel drive 1000 housings have the 4 bolt holes for the parking brake mount on them, and use the GM C5 apply piston design the TCM is calibrated for. Also keep in mind the 2400 will require you to swap the 1000's gears over to the 2400's output shaft then re-assembled. I personnally would jst find a 2 wheel drive housing off of a 1000 as I'm sure you could find somebody willing to trade. In fact, I think Eric from DURABURB has several hanging on the wall as he converts alot of 2 wheel drives to 4X4's and I believe I remember seeing a stack of them when I was in his shop.
1995 K2500 SUBURBAN, LB7 DURAMAX/ALISON powered