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I was leaving the valve stem seals for when I do the rebuild


Unless your compression check shows something bad, your engine probably doesn't need a rebuild. Replacing the valve stem seals while you've got the plenum and timing components already off makes all kinds of sense, and will likely have the engine in a condition to go another 100k miles with no problems.

95 Montero SR
3.8 MIVEC, Advance headers, 2 1/2" exhaust, Magnaflow muffler, OME shocks & rear springs, 2" body lift, 3" tank lift, 4.90s, TRE front locker, factory rear locker, Roger Brown Rock Sliderz, 315/75r16 (35") tires, Sport big brakes