Hi Jack,
good to see your'e progressing on your build.
One thing I found the hard way after all that you have done with tight gaps anxiety and all is that you will find that very high stresses will come to bear on the hatch rim corners/edges as you pull up one side to get into them ,the other side will roll out of it's location and if it binds on the rim will make for some bruising of the epoxy.The other thing I recommend is to glass over the raw edges as this is a high stress area subjected to the afor mentioned so de laminating from the wood.
This all means your [nearly]invisible hatches will need a good amount of working clearance [3-5 mm?] so you can use them in the field without this kind of damage being likely.My hatch design may have meant I had to do this.Yours may not be so sensitive but check how it will work in order to discover what clearances you might need.Include enough for the glass wrapping as well.
cheers,