The Stovebolt Site Forums The Shop Area The Electrical Bay getting wires to doors

As Rusty mentions:

This

or this

The basic idea, also used in Tim's rear door metal coil example, is to have the jamb end fastened and the door end sliding/floating in and out of a hole/sleeve in door.
As far as Tim's mention of coil. I have had several TF barn door suburbans and panel trucks, I have used the old fashioned tubing benders, which are still available, as a loom. They would be pretty noisy to use on cab doors.
There are some tail light looms that could work.
I searched door popper, electric window and lock, aftermarket companies.