In my 66 Overlander overhaul, I added A/C and plan to replace the old oven with a microwave. The old service looks to be a 30 amp main feeding two 20 amp breakers. I still need to hook the 120 V A/C (the top wire coming out of the wall) to the panel. Do I stay with a 30 amp box with more 20s, or do these upgrades force me up to a 50 amp service? And should I run a dedicated line to the microwave? Any help is greatly appreciated.