How do I find out what gear ratio I have in My drives.
They are twin Merc 888/ 302 I Think that is pre alpha?

it should be stamped on the side of the drive with the serial #, if not you can take the top cap on the drive off and count the teeth on the gears, I would guess they are 1.65:1.

http://www.perfprotech.com/store/ass....aspx#assembly

According to the parts manual those have a 1.5:1 gear ratio.Gear set is parts #22 in diagram.If you want to check put it in forward and crank the engine over by hand.One and a half revolutions should turn the prop one.Those drives were made from 1971-1977.I was surprised to see most parts are still available for them.

This place also has the stickers you were looking for on Speedwake.http://www.perfprotech.com/store/ass....aspx#assembly