Just did 2 to 4 bbl swap car starts wont stay running please help

since you changed the intake and the carb and added a lokar throttle cable, I would go with what magnumdart suggested. Make sure the cable and the idle screw is setup correctly. This will most likely be the reason why it won't stay running after you let off the throttle.

If that is all taken care off, maybe check for vacuum leaks around the intake and the base of the carb and fittings, you can do this by spraying some water on the area while the engine is running. Any change in RPM suggests a leak.