I would do something different with the amp and instead of a cap I would rather have a battery.
you can get a crescendo bc2000D for 340 shipped that is a couple hundred cheaper than the Rockford. That would allow you to do a battery instead of a cap or savings towards a H/O alt.
i would take his advice, save money by using Crescendo, AQ, Ap, or anything not RF.
i know their amps are amazing but for the price of the amp only being 1500-2000 rms, which you probably wont see after rise, you can get a higher rated amp, especially Crescendo, that ll more and then some.
also, look in the for-sale section for some good deals!