I decided to install the optional flaps. They are not needed for flying, but I think they look really cool....

Here's a sequence of making them. I found that cutting a template and then using a light spray paint mist to mark for ribs and voids saved me some time (it's a "labor of love" right...)

The humidity this summer was very high, as can be seen by the warp in my balsa when I got home the next night to add the ribs to the flaps. But no worries... that's what ribs are for, right?

The final picture shows me cutting out the 1/64" ply "top" piece. When those flaps drop, this bird will look realy nice from the rear! Thanks for a terrific plan Dave Platt!