What size are the Woodruff Keys between the Shifting Yoke and the Cross Shaft?

[mwh2319]

RE: Reversing Gear

I’m trying to replace one key without having to take the other key out in order to figure this out.

Also the Universal/Westerbeke Parts List, July 2010, page 132, says there are four Woodruff Keys, but I’m fairly sure there are only three. Two at the Shifting Yoke, and one at the Shifting Lever.

Thanks,
Mark