emergency brake strut slipping under reaction plate

Has anyone had this or know how I fix it? I replaced my shoes recently, (BOSCH BS871), new hardware kit, c-clips etc. Everything looked good and worked fine, then the e-brake went soft. pulled the drum off and saw the brake strut had popped out of place, slipping underneath the reaction plate (Red part is now under blue part in pic), on both passenger and driver side. I popped em back in place, and the same thing happened again. I bought an OEM hardware kit, thinking maybe some of the springs were weak in the generic kit, but it looks identical, and the same thing happened. Brake had been adjusted, worked fine, 4 or 5 clicks when pulling the lever, then after a hand full of uses it goes out.
The only thing I can think of at this point is that the brake shoe plate is just a tiny bit thinner than the OE. When the C-clips are in place and everything is sewed up, there is some lateral play, I can push the reaction plate and brake strut in and out a bit.
Any ideas? I'm going nuts.

 

Need more pictures if you can.

 

Thanks Bishop84, I'll take the drum off in the morning and take a few more pics.
Maybe "behind" would be a more accurate description, than, "under." The tip of the brake strut is now behind the reaction lever.