OK, I found the pics that started this. initially I saw drawings from some military spec sheet for the L 42 and it described a set up like this, a plate the same area as the front of the TG, 1/16th thick, but even though I later found L 42 images I never could find out what the wood set up was supposed to be underneath or how this was supposed to be different than not having the plate, the area's the same after all.