My brother gave me a roll of 8/3 with ground. I want to wire a sub panel in my garage for a Millermatic 210(30 amp input), a 220v 20 gallon air compressor(15 amp input tops) and a dedicated 20 amp 120 volt recept. Bought a 6 circuit main lug panel. Anyway, was gonna put a 60 amp breaker in...