have to move my harman XXV out from the wall further.didn't know i had to clean a fines box and the blower fan,the installer never said anything,so,i had him put it 12 inches from the wall.well at 6'3" and 300lbs i cannot fit or have any room to do this.anyhow,going to add a 12" pipe to space it out from the wall.what silicone sealer do i want to use on the pipes?i see rutland makes a 600 degree black and red?is color the only difference?i also see alot of 500 degree silicones,is 500 enough protection?input always appreciated