DASO,
From your introduction photo, I can see that you do have a 3A frame.� Edit...it could be a very late 2A frame also. More pictures would be needed to be sure.
Over a 70 year period, many changes, parts swaps, modifications can happen.� It is uncommon to find an old Willys that hasn't gone through a number of changes.� That starter is an MZ4113...the common starter for a 2A, but it can be used in place of a standard 3A starter by adding a starter solenoid and, in some cases, a different flywheel gear.� Your engine may have also been transplanted from a 2A.