I saw that on my -6A but not on the other models. However, it's not hard to deal with. Don't dimple the skin or the rib there. The thicker rib lets you countersink. Proseal and rivet the rib to the skin first and drive those rivets as much as you need to; you have extra strength with the proseal and the T905 has to get past those skin rivet shop heads. Now proseal and rivet the attach angle to the rib. It's worth your time to make a fillet of proseal along the inside of the end ribs and a smear of proseal over the rivets on the inside as well.
Another thing that may help (I can't tell from the picture) is to radius the edges of the bracket where it nestles into the rib, which can prevent it from resting against the rib web.
