our jeepster has had several engine swaps, chassis swaps and is now on a blazer chassis and it was too much work, I've had jeep wagons, pickups and a FC pug nose truck. lots of modifications. I don't know if there is enough clearance in the jeepster floor for the 4 X 4 parts. If it is to stay 2 WD I would look for a 2 wd trans. A few years ago Ford was having Supply problems and put the trans and T case out of 4 wd into 2 wd Bronco II's but they didn't have the front drive shaft yokes and I don't know what if anything other than an output shaft was inside the T case they used ... MY Jeepster originall had the 4 cyl and OD trans and VW bugs could pass me on hills.
My first swap was to a nail head Buick 364, Ford station wagon T 85 Od trans, 9 in rear and the Ford brakes on the front.