I'll apologize before hand for partially derailing this thread with this post...
So, it hasn't been fully tidy'd up as of yet (I still need to cut/fab a cover over the radio bodies and a better "holder" for the mics when not in use); but here's a few quick pics of the setup:
Radios: Midland MXT275 for GMRS | Uniden CMX760 for CB
Antenna Mounts: Tram 1246-B Trunk Lip NMO
Antennas: GMRS Daily - Browning BR-2445 | GMRS Trails - Browning BR-1713-B-S | CB Trails - Browning BR-140-B
Both antenna coax come in on the passenger side firewall grommet, across under the dash and down the center tunnel. A small (1/2") hole was drilled in the bottom of the center console cubby for all the wires to come in and the little piece of carpet at the bottom was trimmed to match. Radios are jointly powered off of the 12v outlet in the center console, each with CAT6 extensions so their remote mics plug in at the side of the center tunnel (GMRS on drivers side, CB on passengers side, aligning with their antenna sides). I still need to secure the radio bodies into place, currently they are just held in by friction/space constraints. And I still want to make a little cover over them.
The remote microphones have Magnetic Mic adapters on them and there is a Scosche Magic Mount on the center tunnel behind the shifter to hold whichever one is in use. I'm a huge fan of the whole line of Schosche Magic Mounts and use them for all sorts of things.
Carefully inspection will notice that the center cubby is the generic storage spot for all sorts of communication stuff... It holds the smaller GMRS antenna and the cap for the CB side when the larger antennas are in use; it also holds my Uniden BCD396XT scanner (as well as it's 800Mhz antenna and 12v adapter), my Garmin inReach Explorer+ (plus it's magnetic mount, backpack mount, and USB charge cable), and my Motorola Minitor V pager.
My Baofeng UV-5R lives in the cubby sometimes, and just laying in my drivers side door the rest; it is programmed with all the FRS/GMRS frequencies (yes yes, technically this isn't "legal" use) and has a remote speaker mic and super short Diamond UHF antenna on it. The 12v battery adapter, full size VHF/UHF antenna, and adapters to connect either it or the scanner to the NMO mounts lives in one of the bags in the cargo area.
Anand: Thank you! This is what I was looking for. Helps a lot with my comm ideas. I ordered the same GMRS and CB the other day. Now I will need antennas.
I think the UV-5R(version 2 and 3) have been FCC approved if you have the proper license.