I recently experienced an abrupt lean condition on the road with my Carter YF 2100S. It kept stalling out and needed the choke at operating temperature. It was running great for about 200 miles after having a bushing put in the throttle body. When I pulled the carb off, I discovered that the guy that put it in only put one on the pump lifter side of the carb. Is that OK or should both sides of the throttle body be bushed?

Also, is it a "best practice" method to use two gaskets, one under the carb insulator with another on top of the insulator when mounting the carb on the intake? I have one under the insulator and another on top of the insulator and I can't tell if the leak is coming from under the insulator or from the throttle body shaft itself or from somewhere else in the intake. All hoses and connections check out fine.

Is it possible to get a fairly good vacuum reading when tuning a carburetor but still have a leak somewhere else that hits all of a sudden and stalls out the engine? Any input you guys would have is greatly appreciated.
Thanks,
Mark

1956 Chevy 3200, 1/2 Ton, 235 CI
https://photos.app.goo.gl/TQQo1YnFjs3U7xB57