RG400 cable access for secondary GPS

At long last I decided to mount a secondary GPS on the top of the roof. A Rami AV801 active GPS unit was chosen. This has an amplified RF output and the preamplifier in the antenna powered via the coax cable itself. I have done this because I lose the chance to do a subsequent install once I rivet the inside arch skin. For now this antenna will be used with the Flarm-Fusion unit that I am installing. Using a splitter and suitable power decoupling, this GPS unit can serve as a source for other GPS-requiring avionics I may install in the future. I wanted the Flarm GPS to have at identical visibility to the sky as the GPS2020 which is a source for the ADS-B out. Midwest panels have advised that they have had visibility issues with alternate GPS antenna locations such as under the dash or forward (!) of the firewall. There seemed little point to second-guessing this assessment. Another motivation is I want to be sure the quality of positional information sent to the Flarm is as good quality as is being made available to the ADS-B in/out system.

So I have begun the process of routing the RG400 cable, making an additional set of holes fitted with snap bushings.