Re: Part number for lower unit seal?
I believe we established in an earlier post that your lower unit is a one piece lower. ---NO shear pin drive on the prop and water pick ups on the side of the gearcase torpedo. Only minor changes were made to this lower unit so the seal is the same for almost all 3 and 4 cylinder engines from 1979 1/2 to 1989. They changed the drive shaft, water pump and probably the seal in 1990.
So if you have the one piece lower unit, then the seal is the correct one.