Clutch is slipping and I need help with diagnostics
So I've got a 1990 ranger 2.9 L 5 speed that i just bought and it had been sitting for about a year. and my clutch is slipping really bad. I noticed a little oil on the filter and surrounding areas so I'm thinking that oil has gotten on the clutch because it's a fairly new clutch but I'm not sure. By the time I got it home which was 6 miles the clutch was smoking fairly bad and had done so for a few minutes. My buddy said he thought it is a leaking rear main seal that's bad and is what caused the oil on the clutch but I'm not sure, which I guess is my main question. What do you guys think? Could sitting for so long ruin that seal and cause this? It also took about a mile for the slipping to become noticeable. Also how long would it take a novice like my self to replace the clutch? Thanks guys.