Help with Amp Wiring

[bzubke1]

Well that little black box on the amp board is the stock amplifier, it sounds fine at low volumes but when I try to play at a decent volume it quickly distorts, so I'm going to go ahead and replace it right away. I am thinking about using the distribution block below for power and ground. For the power side, let's say the amp I get for the cabin speakers requires a 50A fuse bringing the combined total fusing up to 185, what size circuit breaker should I use? 150A?
http://www.sonicelectronix.com/item_...00-CPS2-2.html

Thanks for all the help I really appreciate it.