Finally have all of the connections wired and (more or less) tested. I’ve added LEDs to the running lights and servos (not shown) to control the couplers. Just need to add about 11oz or so to the fuel tank and put it all back together for final testing. I’ve attached a programming cable to the microcontroller board so I can download new builds or tweak the s/w if required. Phew. This has been quite a bit of development. The control widget itself went through many interations (see controlwidgets.com) as did the power board. I’ve settled on the Pololu 18v7 programmed to only give forward motion with a relay switching between forward and backward. Anyhow, soon we will be doing some real world testing.