I ran a ground all the way back to the front.
I went to Autozone and found some 20', 2 ga., jumper cables for $40.
Kinda hated to whack the ends off, they were really nice.
I ran it along the frame rail up high to protect it.
Then when it enters the engine compartment, I used some Thermo-tec Thermoflex tubing to protect it from the downpipe heat.
I then used 2 stereo power dist. blocks to connect everything.
If you really want to avoid the possibility of electrical gremlins, I would go this route.
The battery is the holy grail of grounds and you'll find none better.