[mild68]

I used a 5.3L w a NV3500 in an S10. From what I have found is the pilot bushing/bearing you use depends on the year of the engine. My trans is a 96 from a S10. The 5.3 is a 2000. I used a flywheel from a 2000 4.8L full size. I got luck w the pilot bushing. It too was from a 2000 4.8L full size, as was the clutch kit I used. Different year 5.3's can use either of 2 different pilot bushings. The one I was able to use is the smaller diameter that fits deeper in the 5.3 crank. Some are a large diameter that don't fit deep in the crank.
Hope that's clear.