[OrrieG]

I would not rush into a complete rebuild if the compression is good and there are no obvious knocks or noises. If the rear main is bad enough to foul the clutch or making a major mess underneath, or a drip now and then just bugs you, pull the engine and fix the rear seal, pull the timing cover to check the timing chain (usually worn, I always replace mine). While the pan is off put in an new oil pump. You can check a random main and rod bearing using plastigauge to see if a rebuild in warranted. You can also check for stamps that indicate previouis rebuilds (bored mains, turned crank and rods). You can also check the cylinders for signs of piston scuffing if the compression is down. If the intake is leaking, that is a good opportunity to check the condition of the cam and lifters for wear. If all looks good, install new gasket set and drive another 50K.