https://www.fish307.com/content/diag..._Terrova80.png
Here is a diagram. Remove 2 bolts that hold seal end on. Hold in on shaft as you slowly remove the housing so as not to pull it out of the brushes. Put a little lube on shaft will make it easier. Push seals out from back side. Then just reinstall. Once done there is a YouTube video on tuning your trolling motor you might watch.