Adding gauges in T660

I'm planning on doing some changes to the dashboard; the main part being pulling the Navplus unit out and going with a 14 round gauge panel. (NP isn't working right anyways, and the weight/restricted road/weigh station dinging is giving me headaches).

I know almost all of the gauges are ECU controlled, but I'm wanting to add a few that were not spec'd on the truck when it was built; Intake and fuel vacuum gauges, and diff temp gauges. My question is how do I tie these into the ECU? I know where the sensors mount, but are there blanked connectors in the harness for these options? And will the ECU need programmed to operate the gauges correctly?
I can get the gauges, jumpers, sensors and connectors with no issue. I'm just wanting to know if it's going to cost a fortune or be a total PITA to get them to work before I drop the money on parts.

Truck is a 14 T660, MX powered.

If this has been asked before, my apologies. I'm new to the forum and there's a lot of stuff here.

 

Good deal, I think the company shop has that. What about the sensor hookup? Should there be connectors I can use, or do I need to find a wiring diagram and CECU pinout and start splicing? LOL

I haven't spent much time underneath the truck, but there seems to be an awful lot of wiring beyond the cab, more than necessary for lights and wheel sensors. I may get back under it soon and look a little closer (just did my PM today and didn't think to look.... Derp. Too focused on not getting grease in my eyes).

 

I'm assuming the gauge is an option, all the company trucks have them. Maybe vacuum is the wrong wording, they are more of restriction gauges for the fuel and air filters. Measure in inches of mercury.