Not sure about the engine swap, but I've seen other engine swaps (Mopar, Chevy, Ford, Mitsubishi, etc.) into both Kaisers and Jeeps, so I'm certain it can be done if you take the time to engineer it correctly.
I believe that AAJ Brakes has recently (past year or so) made a front disc conversion kit for some of the Kaiser cars.
(503) 890-1469 or
AAJBrakes@comcast.net - He is in Portland, OR and I've spoken with him on Chrysler based kits.
Another company to talk with is Scarebird.com
sales@scarebird.comThey are located near Seattle, Washington and I spoke with them several years ago when I was looking to convert my '49 Dodge to front discs. Their kits are bolt-on, or near bolt-on without the need to cut up your car. When I spoke with them, they were just getting a customers Chrysler in to figure out a kit. I spent the next 2.5 months working on a bolt-on design myself and when I got the design right, I couldn't get anyone local to cut the brackets to mount the calipers. When I called them back, they had just gotten their kit back and had brackets ready. Their design and mine were almost identical, with the exception of theirs using bearing adapters and mid 70s Mopar hubs and rotors. I bought their kit ($185) for the brackets and purchased the calipers, pads, and the rotor I had come up with from my design and put everything on my car. It bolted on just fine and the only change I had to make to the car was to adjust my steering linkages (turn each side in 1/4") to correct the steering. Total cost of the kit and parts from the local autoparts store was $400.