"Jason... Having the shift rod
"Jason... Having the shift rod up, down, or in neutral when removing the lower unit has no bearing on the shifting aspect of the lower unit. Having the rod in reverse simply makes it easier to obtain access to the top of the shift rod.
However, if you turned that rod..... that would absolutely affect the shifting as the height measurement is critical.
I don't have the actual measurement for the 1983 model, but the following measurement of the 1981 and 1985 unit may be the right one for you. I'll list what I have but I'd suggest that you check with your local dealership to make sure the measurement is right. The measurement is to be from the upper surface of the lower unit casing to the center of the shift rod hole, with the unit in neutral and the rod offset to the rear.
1981 - 50, 55hp Manual Start:
(Short shaft) 16-23/32 - (Long shaft) 21-23/32" plus/minus 1/32" Have the shift rod in neutral and the offset to the rear
1985 - 40, 50, 60hp = (Short shaft) 15-29/32"
(Long shaft) 20-29/32" plus/minus 1/32" Have the shift rod in neutral and offset to the rear.
As you can see, there is about a inch difference in the measurements above, pertaining to the different years. I would think that your engine would line up with one or the other. Let me know.
When installing the lower unit, have the shift control in forward so that nothing is in the way of the shift rod when you're pushing it upwards.
There is no reason that there would be a gap on either side (crooked lower unit) of the lower unit when it's being installed. It should slide up easy and even.
Joe
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