a cautionary tale: I lost count on how many times I rebuilt the carb on my '48, probably did it every year from when I got the truck roadworthy in '98 all the way to '09. It idled fine, it was responsive on the road, and fired up quickly in the cold and hot (after years of struggling with hot starts caused by the original battery cables). The problem I had was when driving down the road it ran fine, but when I'd hit the brakes, the engine would stall; the only way to counter this was to open the throttle to get about 1500 rpm at 'idle' rather than the factory spec of 450. After being stymied for over a decade as to what was causing all of this, I finally threw down $20 on an old B&B carb on eBay, picked up another rebuild kit, and rebuilt this 'new' carb. Over three years later, that carb fires right up, idles fine, and operates as required while driving down the road without much of a pucker factor when approaching a stop light. My best guess is that one of the fuel check valves (them little b-b looking gizmos in the rebuild kit) would get stuck in its passage and choke the fuel supply leading to the main jet; either there was some debris in that passage that I couldn't see to remove, or the passage had eroded from being gummed up from the truck being parked outside for over 20yrs. Not that you should condemn your carb now, but finding another carb to rebuild may be an option in your future, or at least have an extra carb on the shelf to experiment with when ya get bored