Originally Posted by SmilingJack
I did exactly like you mapped out.
For 1,2 & 3 I used #2AWG
Ditto above. I would run a second #2 wire for the airframe ground from the negative battery post forward to the firewall. Do not ground the battery locally at the rear battery mount. It will eventually let you down. Ground all your avionics etc. at the firewall terminus of the ground wire run. Some things such as landing lights, nav lights etc. can be locally grounded, but the important things should be grounded at that firewall ground terminal. This will keep radio noise, ground faults and other gremlins at bay.
Be sure to ground your engine crankcase and alternator frame to this same terminal.
Mannan J.Thomason, MSGT. USAF (RET)
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