I have a KXPA100 amp. I am trying to mount it. The manual says - "The bushings are threaded for 8-32 screws. Do not use screws that extend inside the amplifier more than 1/8" (3.2 mm)." I bought some 8-32 thumb screws from AMAZON and they are too small. Did AMAZON do me wrong, or are the holes another size? Thanks, Kent KQ4KK