I use Spicer balljoints. Never seen a non split cone, I would find a split one. EMF in Canada makes the best balljoints, not sure if they do the old style Dana 44 version.
The inside of the pistons rust and cause them to stick. You can take the piston out, clean the rust off and reassemble or just trade it in for a new caliper.
If you pay someone to do it right, the labor cost is the same as a hp dropout. I have done it on a solid axle 2nd gen with leafs and the diff side housing is rectangular, not round. So making perches, ubolt top and bottom plates are a bitch.
After Laserfab picked up Airbus as a priority customer I started having Tacoma Steel do all my cutting. They have good prices and quick turn around time on 3 lasers, 2 plasma tables and 2 torch tables.
Novak or Advanced Adapter and a Dana 18 or 20.
http://m.ebay.com/itm/Muncie-4-speed-with-Advance-Adapters-Jeep-Scout-Dana-18-20-transfer-case-adapter-/360661228535
Another thing is that you can remove all the emissions and pcv crap. Propane is real sensitive to vacuum leaks. And some samis blow blue smoke because of the pcv system. Mine will run on the rev limiter at 6000 rpm with no problems.
I have a samurai with a got propane kit. I can swing by your place next week if you cant figure it out. Id say ditch the shutoff until you get it dialed in. It is normal to crank and pump the pedal for 15 seconds or so if it is cold. Push the button on the vaporizer and it should help start...