my front driveshaft was 3" too short. so this is what i did...
i cut my driveshaft in half..
then cut a piece of tubing 5 1/2 inches long..
then lathed it 1 1/4" on each end to slip into each end of the driveshaft pieces..
then i welded them together..
then painted it..
then painted the yolk to match..
the driveshaft fits perfect now with about 1" of the yolk splines still showing. i have a 1986 Samurai with a SPOA YJ lift with missing links. it ran okay today in the yard, didnt seem to vibrate at all, but we'll see how it holds up when i get on the trails!