need working carburetor

[Guest]

My 1958 with 390 engine runs terribly. The carb "expert" who rebuilt the Holley that came with the car claims it ain't the carb but I've eliminated every other possibility and he's being stuburn and refuses to lend me another carburetor to test my theory. I'll even pay rountrip postage to borrow a carb from someone on the list just to try and see if it solves the poor performance.

Thanks.