From personal experience I have had MSD strand me 200 miles from home & you cannot walk into mst parts stores & get parts , so yes I would rather have a Mopar system & carry some extra parts rather than a spare MSD System .
You need to start checking things fisrt
The coil should fire with power on & the negative wire disconnected , if you use a jumper& ground the negative side of the coil for a few seconds & break the ground the coil will fire if it is good , Check the gap between the rotor & pick up , it should be .008 , fold a piece of paper over 2-3 thicknesses & you will be close enough if you don't have a feeler gauge , if you pull the dist & & spin it while it is plugged in the coil should fire multiple times , check the ground on the ECU , the body has to be grounded to function properly .