Hi I have my battery relocated to the passenger bin and also wanted to upgrade my grounds. Question is could I go off the negative battery terminal off the wiring harness thats still in the engine bay and ground to the block and then run a cable from the negative battery terminal in the pass bin to the downpipe and then to the starter?

 

Ground the battery to the floor pan in the bin. It's that simple. The positive needs to be run all the way back to the engine bay.

 

Yes, this would work fine. As mentioned, grounding the negative terminal to the body when relocating is pretty much the standard. Grounding the old negative wire to the body in the engine bay is also a good practice. As well as, body to engine in a couple other points.

 

i already have it done i was just gonna add more grounds