The crossmember from the K10 2wd front end with all the suspension components can be removed as a complete unit and bolted to your frame. You should be able to do it over a weekend. You may have to drill the bolt holes in the frame if they're not already there.
I have seen some of these K10s lowered but to get a real low rider you might have to change to the MII front end kit.
The rear end is the same for a 2wd as a 4wd. The rear mounts under the springs. You can lower the rear by mounting it over the springs. Cut off the spring pads and weld them on the other side of the housing or use a car rear end that already has the pads on the bottom. Welding things on a rear end can warp the housing if you're not extremely careful.
If you're getting that Jimmy for a good price it's a worthwhile project.