So, I hated the Sportys timer I had, with a passion. I really didn't know a person could have so much disdain for a simple clock/timer. Apparently the avionics guy somehow crushed it when he moved it to do the panel work. Biggest favor anyone ever did for me. Anyway I bought a AstroTech LC-2 to fill a panel hole, it says it runs for 2 years on battery (or can be hardwired). I'm assuming I need a new W&B complete with IA signature to screw this thing into the panel battery operated correct? What does the FAA consider negligible? This is just a minor alteration right? No 337 or STC or any of that needed to install it correct? It weights 0.25lbs