ORIGINAL: Craig-RCU
I agree with bigtim that the two screws in the spar will not be a problem. Looking over some of my build photos, I noticed why you might want to beef up the ribs if your going to add aileron servo hatches.
I should have included that as well, in the area where the hatch landed at the wing rib, I added a strip of wood that allowed the hatch to sit on so that the hatch matched the curve of the ribs.
I did this after I sheeted the wing so I could cut the hole out right next to the rib,then glued in the doubler strip,it wasn't large just 3/8" wide and the length between the hatch mount rails,it was easy I just cut some scrap to length,held it in place,and traced the curve of the wing and cut it out,the crutch really helps the hatch conform to the very slight curve of the wing.
after installing the doubler strips, I cut the hatches out so they were a very tight fit, so little paint wouldn't seep into the seam,they havent been removed since the plane was painted.
if I need to open up the wing for some reason I am going to have to do some fine exacto work to free the flap and servo hatches,there locked in there tight.