On those support ribs, don't forget to drill a 1/2" to 3/4" hole in the rear section of them so you can route the aileron servo extention I almost forgot to do that!
I don't really know why they designed a bolt to go through the top of the wing into the mounting block of the retract mounts. I didn't really think it was necessary but I did it anyway. Here are a couple of pics of the install.
You can see how they are installed here. Also, there are some 4-40 bolts and nuts going through them to make them stonger so you only have to use ca to glue the blocks one. The holes drilled for the aileron servo extensions are out of the camera's view. The blocks are drilled and tapped for a 10-32 nylon bolt for the retracts. Nylon bolts are a very good idea here. I would rather the bolt break on a bad landing than to tear apart that foam wing!