motor wont stay running
Wired wrong. Some of the diagrams shown for that setup are misleading
THERE IS NO NEED TO CHANGE THE WIRING specific to the original ballast resistor. If they gave you a new resistor, simply unhook the old and install the new. Then run the power wire "from the box" to the "key" side of the ballast or to the IGN terminal on your voltage regulator
SIDE NOTE CHECK for voltage drop. Turn key on, engine stopped. Check voltage at VR "IGN" terminal. Compare that voltage to battery. Should be within 3/10 or less "same as battery." If not you have a harness/ voltage drop problem
Additionally make SURE the ECU box is well grounded. MUST be grounded, as well as the VR