You can't rely on the ebay "rebuild's" either. My friend bought one for his 72 truck w/400 Big Block. It looked brand new, they machined off the stamping and assigned their own number. We installed it and messed with it for a half day and it would not run. The best we could do was a little above idle for a few minutes. We took it to a friend that has 50+ years rebuilding carburetors. He disassembled it and only thing he could find visually is that it had a Buick base but couldn't see any obvious reason it wouldn't work.
He ultimately obtained another Q-jet and it started right up and runs great. The ebay special is available if someone wants it for a door stop.
Fred
