RE: Break-in on the ground or in the air?
Use the gas / oil mix you intend to use long term ... I prefer something in the 32:1 range. Set the needles for normal running .... not rich like you would a glo engine. Make sure the engine is reliable on the ground and go fly. Don't beat the crap out of the engine for a few gallons and thats it. You don't have to baby it but certainly don't abuse it! Enjoy!
Of course make sure the engine is properly cooled in the plane with proper air inlets, outlets and ducting / baffling as needed.