I have a Craftsman 6.75 22" mower - self propelled, model 917.377690 with a Tecumseh engine. I bought a carburetor replacement kit. I am trying to refit the plastic bowl (kit) to the metal carburetor in the engine. I can't get it to snug up. It seems as if the main nozzle isn't fitting into the metel carburetor and the whole bowl assembly is pivoting slightly but not allowing a meeting of parts. I can't get the spring to attach because of this. Can you help? Thanking you in advance.