2kMax

well I have a little idea about what I am doing but i still want to make sure i am doing it right.
Here is what i want to have answered....
I have a 4th gen without bose and i changed the speakers to eclipse 6.5 coax and kicker coax in back. I am soon getting a clarion DXZ835MP headunit or something along that line and i wanted to amp the speakers i have now. Do i need to get a 4 channel amp to do so??
I am also getting subs in as well so a cap is a must i take but is using a double fuse the same?
Well if anyone can answer these questions please IM me at krazyiekrn on AIM preferably.

Thank you very much in advance.

Kiwon