I recently created a new module with 8 adjusting legs (yes, it's a rather large end loop).
Here is a before and an after photo showing how I chose to conceal the holes.
You can see the 21/64" hole and the tree stump attached to a 5/16" dowel that's about 3/8" in length. I attached the stump to the dowel with thick AC adhesive.
Here is the scene with the plug in place. You'd never know there was anything there.