My car had 1 amp (2 chanel), 1 sub, 1 head . Now i got another amp (4 chanel). Now 1 want to use 4 chanel amp for font and rear speaker, another for the sub. Can someone help me with that. How to run wire. My old amp is Boston GT-20, stock speaker, new amp Kenwood Exelon KAC-X541, sub Boston. Hope someone expert in audio will help. Thanks alot