The Mac 32 chain saw has a couple different variations. One earlier one has the carb on the front (flywheel side) and the exhaust on the back. Later ones had the carb on the left of the cylinder with the exhaust on the back (chain side).

The 32/28 string trimmer has the carb on the left and the exhaust on the right. The muffler is held on with a spring.

The 32 blower had a bolt on muffler.

Generally, on the string trimmer, the 28 -32 jug/piston are interchangeable on the same crankcase.