I would like to step up in power with another Mac amp. I have the MC152 now. My main problem is my rack is 10 inches from shelf to shelf. The amp can't go on the top shelf either. There is no room for a power amp stand on the floor. I can't swing the cost of MC301s. The newer amps are all 9 7/16 inches in height. I don't want to squeeze anything in, due to heat concerns. Any suggestions or ideas?