On my 02 there are only two factory ground wires.
The zero gauge, large wire goes to the power steering bracket...
The smaller 10 gauge wire goes directly behind the battery to the firewall...


I added a 4 gauge supplemental ground wire from battery to the fender...10 gauge for all the accessories, potentially, seemed really small to me.

 

Although this looks a bit different, this is your ultimate goal for that extra pigtail wire.