Need a little info. I have a 89 Jeep Cherokee, working on putting a system together to drop in it (already has db drive speakers all the way around). I will have 3000 watts RMS in my sub, along with a 2500.1 mono block amp. I plan on using 2 gauge wire, doing the big 3 upgrade with 0 gauge. Question is ....is this the point of upgrading the alternator and battery? If so, how do I determine the output I need? Thanks for any and all help in advance