Starting with the flaps because they are the easiest closeouts to get started with, we dug out some premade FL1 and FL3 jigs.
The first actual construction step in the accelerated kit is to dig out the closeout area, exposing the rim trimmed with peel ply and also exposing a supposedly pre-existing flat plane within the foam core onto which I will mount the flap hinges and closeouts. For all these dig outs, I used an Xacto blade to the approximate depth creating crisscross pattern which I then dug out with a flat screwdriver.
A closeup of digging out the peel-ply. Note here that the subcontractor that made the preskinned kit did not use colored peel-ply, leaving me with the perpertual question: Did I get it all out?

I was very relieved to have Russell looking over my shoulder!
Ok, so my first flap dig out did not leave a perfectly smooth surface. I guess this is what dry micro before slurry seal is for!
By halfway through the starboard flap, it was looking better. I could even pull fairly long pieces of peel-ply off (below).