Don’t confuse Fixed Station with fixed location. A Fixed Station is not the same as a Control Station. Nor is a Fixed Station the same as a Base Station. All three are located in “fixed locations” but all three serve different purposes and have different limitations. A Fixed Station is limited to 15 watts and is required to only communicate with other Fixed Stations. Base Stations and Control Stations may have 50 watts and are used to communicate with other types of stations.
So it’s possible for a station at a fixed location to change from a base station to a control station strictly based on usage, and back again on the next transmission?
So could that same station at a fixed location become a Fixed Station on the next transmission?
Welcome, Nate!
If I were you I would find some Notarubicon videos that address your interests. He has them on many different topics that relate to GMRS.
Of course the regulations specific to GMRS are here: https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E
Yes, each park has a designator. You don’t need to worry about the coordinates, just give the designator. And if you do a “park to park”, record the designator of the other person’s park.
Honestly if you’re going to do anything that’s more permanent than peel and stick you should really just punch a hole and install a through-hole NMO mount like @gortex2 showed.
Perhaps an iron or aluminum bearing epoxy would negate that issue. I don’t know of any commercial epoxies that contain aluminum powder, but JBWeld has iron powder in it.