Obviously, Lionel could do it. As Jon says, it's the same board, just different code. Only Lionel has the code to load into the board for the powered unit.
Yeah I know, it'd be awesome to have work exactly the way it was intended, right mown there's I Mars light just solid, I'm gonna modify the light board in the use to have the headlight and Mars light on at the same time with one output then I will swap out the wires on the plug so the market lights are on in forward and the headlight is on in reverse
You could use the Ngineering.com MARS light simulator to fix the MARS light. 
Funny you should mention that, I was thinking about adding s Mars light board I just could remember who made it
Almost be easier to just run a consist. Not sure why I have aversion to that
I'm not sure why you resist that either.
The MARS simulator is my solution for MARS light upgrades. If I do my diesel upgrade board, I have a pretty good simulation coded that I'll include as part of the software.
Actually John, I dont have an aversion to consisting I just think diesel sets that always run as sets should be one diesel like MTH does. Ill never run them as single units and it makes life that much simpler.
The Legacy sets are configured as a consist, the units run independently. OTOH, each powered unit stands alone and will run by itself. The MTH A-A or A-B-A sets with more than one powered require them to be tethered and the trailing slave has a slave board. I'm all for getting rid of the tether, that's a major PITA with the MTH diesel sets.
Right, but the board software runs them as a single locomotive. headlights, couplers and all and for all intents and purposes, the are one locomotive. When you program the set out of the box, you set them all to the same TMCC ID. Its really slick and simple and thats what I like about it.
We are talking about the engine with the RCMC board and motor board sensor and not modular boards with an R4LC.
