GM 8 PIN HEI RELAY?

I am going to ditch the MSD 6200 on my Barracuda for the GM 8 pin hei. @TrailBeast offered a kit at one time for this conversion. From what I have found on the internet about his conversion vs. the one on the Slant Six site is the relay. I already have the heavier gauge wires for the MSD box (negative ground and constant positive). Planing to use a relay triggered from the ignition for powering the 8 pin module from the large gauge + and the large gauge for the ground. Where the MSD box was mounted I am looking to mount the module on a heat sink with two relays, one for backup. Is this overkill? or should I just pull the power from the ignition wire source and eliminate the large gauge wiring? Also the coil is a MSD Eliminator SS.