What electrical upgrades will I need if any?

[Romeo11]

Currently have a 2004 grand cherokee and I have a kicker cx1200.1 amp hooked up to 2 comp r

s with a 120 amp alt and a normal battery, have issues with headlights dimming. Just want to get a new amp and subs. Planning on around 3500 rms and would like to know what electrical upgrades you guys would suggest I do first?

 

[Hertz Mafia]

Big three

AGM battery up front

240a+ alt

 

[Boomin_tahoe]

Dam, more electrical questions!!

And big 3 should use 1/0 OFC wiring for best results.