How to determine the best overall working length for your hydraulic top link is to get the true mid stroke pin-pin distance.

The best way to do this is to have your tractor hitched up to your box blade (as an example) have the implement level with the ground front-back and side-side. Have the implement on the ground, measure the pin-pin distance.

Based on the pin-pin distance, the best possible working length of your top link can be determined.
Fit Rite Hydraulics