The challenge of any other avionics shop doing this is their local FSDO approving it. Stein is a very large and professional avionics shop that goes above and beyond when doing avionics installations. This includes full wiring diagrams, so other places can do repairs or upgrades far easier. This is just one of the reasons why they’re able to get approval. The other issue is that many FSDOs just prefer to say no to everything.
