Hatch Trimming Question

I am looking at using Steve Frederick's method for my hatch sealing system. I can see exactly how it works with a woody where here is no metal trim. Unfortunately I see lots of potential problems when you skin and trim the sides and the hatch. I am imagining that it puts out all the gaps and distances.
So, just wondering if anyone knows of a Build Journal (I could not find one) that shows how they did it or can anyone provide me tips on what needs to be modified to do it.
All the best
Laurie
So, just wondering if anyone knows of a Build Journal (I could not find one) that shows how they did it or can anyone provide me tips on what needs to be modified to do it.
All the best
Laurie