Just got my 1986 GP back from the shop. Had the motor (305) rebuilt. Ran like a champ for about 300 miles, then in the blink of an eye, it started running really rough throughout the driving range and wants to stall at idle. Took it back to the shop and the mechanic checked compression, timing, spark plugs and wires and said the problem was the carb. Carb was rebuilt about 5 years (30k miles) ago, and was working perfectly both before and after the engine rebuild. I'm no mechanic, but I know this car. Doesn't "feel" like a carb issue to me. Anyone have any ideas before I go throwing more money at another carb rebuild? Thanks.