Maybe you can help settle a bet. I'm in the process of having a between-the-ankles radio box and transponder installed in my experimental-certified Pitts (I am not the builder, so I don't have a repairman's certificate). I think this work requires only an A&P signoff, but others think this modification will require a Form 337. Who's right?Also, I'm planning to have just the empty box installed first- no transponder, no wiring, no nothing (I'll fly it to the avioncs shop later on to finish the work). What signoffs, if any, are needed to fly the airplane in this state?
Thanks in advance.
Tom P.