best way to ground a head unit

edubs

Do I cut off the connector and ground through the wire harness or do I use the head unit connector and just screw the wire connector to the car.

Yes.

edubs

Does it matter either way?

It's more or less installer preference:

• I tend to cut the connector and splice to the factory harness - reasons:
  • You can be pretty sure the factory harness goes to an approved grounding point - not some bolt that hopefully hits ground along the way.
  • If you ever want to put the original radio back in the car, or move the new radio to an identical car, you just unplug the adapter plug and don't have to hunt for a socket wrench to take the bolt loose to remove the spade lug.
  • Mechanics that aren't familiar with car audio will be able to remove the radio more easily (if they don't see that they can disconnect the harness from the rear of the head unit).
• Advantages to the other method:
  • Quicker - you don't have to cut and strip another wire and solder or find a quick crimp connector.
  • Theoretically could provide a better ground for high-powered HU's as the HU ground wire might be thicker than the factory wire and almost certainly will have a shorter grounding path.

I've never really heard advantages either way, but there was a recent thread where the factory wire worked and the bolt behind the dash did not.

Hope This Helps!!!

Anyone else have suggestions?