During assembly, they have you modify the center two floor ribs to accommodate the control stick assembly. A while back, I noticed that the WD-610 control column was rubbing on one of the ribs where you fabricate and install the F-716B access plates.

I had removed the access plate and relieved the rib slightly to eliminate the interference. All good, but then before I reinstalled it, I stupidly crawled into the tailcone to do something or other rand slightly bent the top of the rib with one of my feet while squirming around. Not much, but it definitely bowed it.

Probably no big deal, but since that's the rib the aileron trim servo screws onto, and in that same general location. Installing that servo deforms the stiffiner thats stamped in that area anyway, so since I had also tweaked it with my clodhoppers it seemed prudent to reinforce it. To that end, I fabricated and installed a doubler that covers the previously flexed area and also picks up the servo attach points.