Jody, close on the pin, the V has a 1" pin, the IV has a 7/8. Marinetrans is right on the money, 2" spacer (he normally is). Hard to tell from a photo, but looking at the prop it almost looks like the prop hub is the same OD as the washer, if so that hub will only fit a small shaft making it a IV like you said but it is really hard to tell from the picture.

I stand corrected on the actual dimentions. But larger pin is #5 and smaller is #4. At least I had that right :-)

Thanks for the clarification. I think you were the one who told me this in the first place anyway.

Thanks for all the input! This drive is on a boat I'm looking at. I will ask them to check the size of the propshaft for me.

Thanks again!