I initially installed a 4 channel amp using an 8ga kit. it didnt take long before i decided to add a sub and monoblock amp. i ended up removing the 8ga and running a 4ga NXG kit from Sonic.
It will be much easier to manage a single 4 ga run than 2 8s. Just make sure you fuse properly.
As far as wiring, take a look at the PAC FRD24 harness.
2011 Mustang 3.7L V6 Premium ∙ MCA (203A)
Ingot Silver ∙ Charcoal Black ∙ Auto
HIDs ∙ Security ∙ Comfort Package ∙ Remote Start
Koni STR.T shocks/struts ∙ Roush DUB springs