It would depend a lot on the amp draw. If they're drawing only 10 amps, no biggie. A 12 gauge wire should be sufficient for that current on that run. However, if you need to run 4 gauge to carry the current to each one, the shortest possible route for that with a much cheaper run of 16 gauge for the solenoid trigger in the cab would be far more cost effective.
I'm really interested to hear what the amperage draw on those things will actually be. They're a motor which means a lot of start up power, but with their particular gearing arrangement, they might not draw much to continue running. Still, I can't help but see you having to run 4 gauge to them. Just look at car audio stuff. For a 16 foot run of power wire for an amp that runs 80 amps of current draw are done in 4 gauge or larger. Those amps are only outputing 600 watts or so rms in class A/B or 1200 watts rms including thermal loses. It doesn't take much of an electric motor to draw 1200 watts of surge.