mako230

My son-in-law purchased a 96' S10, 4x4, 4.3 engine, 5 speed manual. After about 3 months he called broke down. Said the truck "stopped pulling". I loaded it on a trailer by wench and told him I thought the clutch was gone. Took it to a guy to have a clutch installed. After 3 days the guy called and said the clutch was good and might be the transmission (which he could not work on). We picked it up and started looking for a repair shop or swap out. The price for swap out is $700-$1100 reman and we could not find a used one. I could turn the input shaft by hand and hear the gears turning and it would shift to each gear. I pulled the drain plug to see what the fluid looked like and only about 8oz. came out. There was a small amount of metal and fiber like material in the fluid. We refilled the trans with Syncromesh and it now turns and is much quitter. My question is: Is the trans shot or what. Is there any way to test the trans without re-installing in the truck? My son in law is laid off and I am retired so money is definitely an issue. Any assistance would be greatly appreciated.