relocating battery

I have 2 gauge for the main but im talking the smaller power that hooks from battery to starter relay. Or can i just link off the big side of the starter up to the relay instead of running the whole length again

The problem is, from your description, some of us have no idea what you are thinking

There is more than one way to skin a cat

I myself see no reason to have a rear mount starter relay with a huge cable just to run the starter.

If you do this, you'll need an actual STARTER relay, like a Ford. The problem with Ford per se is there is no easy way to incorporate the original Mopar neutral safety, if you are automatic, or have a clutch safety switch.

In that case, you'll either need to leave the original Mopar relay in place, and use it to operate the Ford start relay in the rear.........

or use a later Jeep/ AMC starter relay which looks like a Ford but has one more (5 total) terminals. This was in fact used in these with Torqueflite transmissions

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BUT I DON'T do it that way.

I simply run one big huge hot cable to the front, and it's hot all the time the car runs. If this is run carefully and protected, no reason it can't be safe..........After all there ARE factory cars, and have been for many many years with rear mount batteries.

If you do it that way, you'll need to run the main cable either to the starter or to the starter relay, and then run a jumper lead between the two. If you run the main to the starter, you only need say no6 up to the relay. If you run the main to the relay, you need a big cable to run the starter between the relay and starter.

PLEASE do yourself a favor and find a good quality heavy duty 4 terminal (properly know as a 2 pole switch) and wire the small terminals to either kill the ignition, or alternator field.

If you have MSD ignition or EFI this is easy.