Mark, you do not mention which throttle/shift unit nor which transmission this is for.
I assume that you are replacing a cable!!!! ?????
As a general rule.... for me, that is....., I begin at the shift unit.
I make sure that the shift unit is capable of giving full "cable travel" in either direction begining from full detent neutral.
The shift unit may over-travel the cable some, or visa-versa! (a non-issue as long as you center)
Again....., the important part is to begin in full detent neutral.
This is the KEY to this, IMO.
In theory, when "neutral" is achieved at the shift unit, you are at the center of cable travel for either a FWD shift or a REV shift at the transmission end!
At the transmission, do same prior to your permanent cable connection!
**Move both shift unit and trans into Full FWD, see if there is remaining cable travel at the trans.
**Move both shift unit and trans into Full REV, see if there is remaining cable travel at the trans.
I now bring the shift unit back into Full Neutral.
With the transmssion also in Full Neutral, I make my final adjustment to the cable barrel fitting (or clevis fitting), and insert into the shift arm......... followed by testing for full travel again.
This should give you full neutral and equal travel for both gear selections.
It works for I/O's as well as I/B's.
Others may have a better suggestion once we know which shift unit and transmission that you have.
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