I sprayed paint on the box, and left a masked off strip at the bottom. The plan is to wire everything from the bottom, and then weld in the bottom panel and touch up the paint at the end.
Here's some pics from wiring day. I made a spreadsheet showing all the needed connections and copied it to my tablet, grabbed some cold beverages and the soldering iron, and went to work.
Made up a pigtail harness for the intercom box
Here's everything wired up. Intercom, headset jacks, seat heaters, switches, USB chargers, and LED lights for inside the box.
This milspec D38999 connector allows the box and all components to be removed from the truck. There's 37 circuits that connect to various hardware outside the box, and this connector packages everything in a compact and waterproof plug.
__________________
1988 "Crane Truck" C30 - 350, SM465, with a 15' knuckle crane -
thread
1986 M1009 - 6.2 Diesel, SM465, 2 speed aux trans, NP205 -
thread
1979 Corvette - 350 T5
1977 Jimmy - 350, TH400, NP203
1982 Blazer - 350, 700R4, NP208 - Totalled, now a parts truck
Scratch built 16' flatbed trailer -
thread