MSD system and stock ECU

I am installing a new engine/trans in my 73 duster, the previous owner installed a complete MSD 6A system (6A, msd distributor and coil). He left the original Electronic Control Unit (Orange box) but cut the distributor wires. I have searched the forums and it appears the the factory ECU is not needed, and not installed when converting to MSD. Any reason to leave the ECU in the car incase of a MSD failure (reconnect the distributor wires just to get home - it may be hard to replace the MSD in BF North Dakota, atleast you could get to someplace to buy a replacement MSD).
Or am I just paranoid and this is the least of my worries on a road trip? Since this is a daily driver, and teenage kids car, I want to make it as failsafe as possible.
Thanks again for the help