MSD Wiring w/ Trunk-Mounted Battery

Good question. I’ve had some strange issues with a couple of boxes I have out there and I’m pretty sure it’s ground issues.

I was told by someone I trust that if the battery is in the trunk you use a 1/0 cable from the battery to a ground on the engine.

Then ground the box to the same ground as the battery on the engine.

I haven’t done it yet.