just did this myself last weekend, when you get the pan off, jiggle the rods where they meet the crank, see if there is slop in any of those connections i heard these motors were notourious for sticking rings so if a ring was draging that could, over time, trash your rod bearings look for aluminum shavings and flakes in the oil pan you will probably find some (in my case i had a freakin pile on the pick up with a 4 mm bolt layin on it) you should also check to see if rods are bent and if you havent done a compression check do one to see what your rings are like there shouldnt be any slop in the main bearings either.