Battery meter max'd out
 

ok so i have the '06 mustang, v6, with the shaker 500. In order to give it a little boost, i installed 2-12's ran a 30 farad capacitor and an amp. Ever since the install my battery meter will occasionally ping all the way to the max voltage level....im guessing this isnt good, but when i tell the car to run the system check, even while the meter is max'd out it still says "charging system ok" I ran the power wire from the battery to the fuse to the capacitor and grounded everything in the trunk. Capacitor voltage usually reads 12.9v but the alarm sounds when the meter maxes out and it reads 14v or so. i did not run an additional ground for the battery and my remote wire for the amp etc is spliced into the accessory fuse on the passenger side kick panel.

1. Why would the battery meter be maxing out?
2. how do i fix it?
3. is there a better place to run the remote wire without removing the stereo or taking the dash apart?

thanks for your help