clotus

Ok so I just purchased an cadence CEQ770 mainly for the aux input for my Roady 2 (sick of the wireless modulator). I also got all the rca cables to connect my HU to the EQ. I have a few questions. I still need the ground wire, where can i pick one up locally, i was thinking just a local shop, or will speaker wire work? Also, I have a kenwood excelon amp for my sub and a PPI 4-channel amp for my speakers, will the 7v output be too much for these amps? I don't want to hook it up to make my system sound better only to fry my amps. Lastly in the install, I should use the ignition 12v connection that mu HU uses, right? Can i just splice into it to power both, will it push enough amps to power both, and it I decide to run my roady though a direct connection with a 12v to 6v reducer will i splice into the same ignition wire? How should this be done, i am hoping to do this tonight, so I hopefully will get some quick posts. Thanks.
-Kyle