There has never been a Factory rebuild kit, because they were never meant to be rebuilt. "Bushing" kits are just a hack job. Put a couple of GM pins and standard sized upper hinge bushings in a bag and "Voila!" a hinge rebuild kit ! If you want the hinges to perform like factory, than you need to build them like factory. In this case a fitted, oversized, steel pin in the lower 67-70 B-body and upper 62-65 B-body.
No bushings. The door check pins (which are custom made also) wave springs are replaced. Here is a photo of replaced parts. Sorry but you can't buy them all because most of these are custom manufactured and not sold retail. This is what I do. Over 20 years now. The first thing required is knowledge(experience). Proper tools and procedures. Proper parts.
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