Transition to wet during home testing

Hi,
Buster has been on 3u ProZinc 2×day, has been on dry.
Starting home testing today for baseline - on dry - it's going well.
This am: test/food/insulin. 356 per Relion Confirm
Testing every hour. When do I feed again?
Also starting transition to dry tomorrow. He'll do it, and we hear not to go fast with this. Any suggestions for a dry/wet ratio at the start and how to progress?
It sounds like we should decrease insulin from the 3u as soon as we start introduction of wet. How much? Of course testing will continue.
Thank you all