Got my lower unit all apart and I am in the process of rebuilding it. The manual says to use a "special tool" to correctly shim the bearing carrier on the drive shaft (whne replacing gears; I am installing a used set that are in excellent shape). It says to attach the pinion to the drive shaft and then use this special tool to set the depth for the engagement of the pinion on the gears. By taking a measurement with feeler guages then adding the correct shim to get the gap correct. Is there any other way to do this than use the special tool? It is a 1978 70 hp evinrude. I called a local shop and they want $85 minimum to do it. I say it shouldn't take more than 10 minutes if I had the tool. I asked if I could rent theirs and they said no. Any outboard mechanics out there that can help me get around this?