I picked up a MMI K-27 the other day, On3, and am considering what kind out layout. I really like the battery RC I have in my Large Scale engines, has anyone tried to put an Airwire reciever in an On3 engine? I think you would have to put it in the tender along with batterys and speaker. Might be able to put it in the boiler, but I don't think you would have the room. If not airwire, is there any other wireless controller so you could use batterys and not have to have any track power? thoughts and ideas?