Here is the adjustment per the Mercruiser manual.
1. Loosen both trim position sender retaining screws
2. turn ignition key to run position
3. trim sterndrive unit to the full down/in position
4. rotate trim position sender as required to show full down/in position on dashboard instrument
5. tighten retaining screws and turn ignition key to the off position.
Sounds like you have another satisfied customer Phebus... Good job.. I'll be bringing my boat by for service tomorrow night.. Thanks..