Compnine.com was a good website with factory diagrams of parts assemblies, OE part number, VIN searches and related stuff. It has closed just recently. Anyone else use that site or know why he closed down?
That is very disappointing. I used that site a lot. Toward the end, they offered paid subscriptions. It was a little pricey for my type of use, but I would have paid for some form of limited use.
There are some other sites that use the same computer catalog (gmpartsgiant.com, for example), but they tend to obfuscate the part numbers.
Comp Nine's "Service Parts Identification" by VIN (that is, RPO) lookup tool was invaluable during used car searches. Now we probably have to go back to the old method of getting acquaintances who work at GM dealerships to run VIS queries.