1. Began installing the three RG-400 coax lines that will go to the GPS and SXM antennas on the firewall. First, I found a grommet that will work, then took a stock stainless-steel grommet plate and opened it up to accommodate a bundle of three coax wires. 2. Located and drilled the grommet cover plate onto the firewall in the upper-outboard corner of the baggage compartment. (I couldn't work out a good way to run the coaxes any other place without them being directly next to either the magneto leads or the fuel pump power wires, neither of which sounded like a good idea for antenna coax.) Located and drilled a matching hole in the bulkhead behind the instrument panel. 3. Installed both grommets and the grommet cover plate. 4. Located and drilled an attach point for an Adel clamp in the baggage compartment, on the upper fuselage gusset. 5. Installed a TNC angle connector on the end of a 7-foot coax. 6. Connected and ran the coax lines for the GTN 650 GPS antenna and the GDU 465 SXM radio. 7. Prepped coax for the GDU 465 GPS antenna.