When you see the carburetor number that looks like this on the tag:
TSX – This equates to TSX-355
3 52
355
One measurement that is most important on this carburetor is the length of the float bowl gasket. They can be 4 1/4, 5, or maybe 5 3/16. This measurement will often lead us to the correct part.
This is just one example of where to find the carburetor number tag. There are several other places it may be.
Marvel Schebler Carburetor Manual
Some MS carburetors have a spring loaded governor control lever which allows for manual closing of the throttle to an idle position for certain type governors.