The base of the doors consist of two parts Andy. The outer one and the inner part. Unfortunately no pics my frined but this is the same way used for making the Fw 190A flaps.
For making the outer part :
1. I copied the scale drawings of it and print on adhesive transparent foil.Then stuck it to the plastic sheet and cut it out. So it was easy as the part had no holes..
For making the inner part :
I used the same scale drawings But... I kept in mind the slightly difference in the part dimensions in order to get the proper size of the inner part that had to be a little bit smaller than the outer one.
1. I copied the scale drawings of it and print on adhesive transparent foil.Then I cut it off and sticked to the plastic sheet. Using a needle I marked points where I had to drill a few holes.
2. With my hand drill and two thin drill bits I made these.
3. Using a scalpel I cut out unwanted areas.
4. Then I used files and fine sand paper for making shapes of these holes and also for cleaning all edges of the part.Then I cut down whole part and sanded in order a little bit down to get the piece much thinner. Finaly I got something like the one in the last pic.
5. Having both parts made I put them both togeteher with small amount of a glue. Later the inner side was sanded along the inner edges of holes in order to get the better shape of it that should remind the embossed areas. And finally I added these small details for attaching the legs.
I hope it helped.