I have a 1978 Jeep CJ5 am working on the rear brakes there is short brake shoe hold down pin and long one which goes front rear?

On a 1978 Jeep CJ5's rear drum brakes, the longer hold-down pin goes in the front, and the shorter pin goes in the rear. This is consistent across most drum brake designs. The longer pin accommodates the slight difference in the brake shoe's placement and the geometry of the backing plate.