What are the sizes of the mounting holes of 10240?

Product Description: 1955-1959 Chevrolet 12 Volt 20 Amp 6-1/8" Mount Rebuilt Generator


For the side with one mounting hole, the hole is 5/16"-24.

The other side with the two holes doesn't have threads. The hole size for both holes is 3/8". They are 6-1/2" apart from each other, while the shaft O.D. is 1/2".