Sorry on the delay: didn't know you asked me a question plus I've been busy working on my new yellow P-38.
With the weight of mine, she gluides forever so I modified the flaps (some might say butcher!) to get more 'down' in them.
I bought the plane RTF but the flaps hinges were connected so the flaps would not fully deploy.
After re-hinging, the internal ball/socket control rod was binding so the flap would not come down.
The angle of the flap control horn was such that it would just sit there when the servo was thrown.
I left the internal horn on the flaps and added surface control horns (at least you can't see any bolts from the top!).
I then cut a hole in the bottom of the wing near the TE and ran a straight connection between the servo and control horn.
Not pretty but the dark blue hides it and I'd rather have a good flying warbird than a pretty one that I don't care to fly!