In my 2010 Titan, Crew Cab, which I had to work out of, I dealt with the same basic physical parameters as the XD and this is how we went about mounting the equipment (I'm not able to provide exact models of equipment but the mounting would pretty much be the same for any set of radios).
Mounted the control head inside the center console/storage area, added two air vents on the passenger side of that storage area to protect against heat buildup when the lid was closed. Power supply wires ran from firewall through inside of console along transmission tunnel to control head and then along trans tunnel to under rear seat. The radio was mounted on a square platform that we bolted to the floor which also allowed us to mount a ground there. I had the factory storage bins so we simply cut out the space for the mounting area and left the rest intake, we did add venting and it should be noted that we used some basic shock isolating feet for the mounting plate. I also made sure the plate kept the radio up off the floor to guard against spills and moisture. Antenna coaxial was run along bottom of the inside rear of the cabin (under liner/headliner), up the side and back across to the exit hole for the brake/bed light wiring. We did have to replace some of the clips we broke when removing and replacing the liner. Removed the light mount on outside of truck, using dremel tool we fashion space for the cable to run out the front of the light assembly and also a relief for a antenna mount. The antenna was a portable unit. We used a quick disconnect on the coaxial which when unconnected was covered by a waterproof rubber cap. The antenna sat on top of a short Z shaped mount that was bolted to the cab inside the light housing. Silicone used to seal around all the access points. Stock light assembly was retained and reinstalled.
When not needed the antenna was removed and the only thing you might see up there was the top of the Z bracket, and you had to climb up on the siderails to even spot it.
This arrangement lasted 4 years before I traded the truck. Only issues I ever had was once the mounting bolt for the Z bracket loosened up and started rattling and once I forgot how tall the assembly made the whole truck and smacked the antenna right off the top of the truck in a parking garage. Oooops.
So the whole mounting was a little more complex than usual portable radio and a magnet mount antenna but it was solid and radio operation was excellent. In looking at my XD this same install would work, just a little more space available.
Sent from my SM-N950U using Tapatalk