2001 WORKHORSE W20 Electrical Systemignitionswitch Problems

I OWN A 2001 SAFARI TREK, BUILT ON A 17000 GVW WORKHORSE CHASSIS. I WAS TRAVELING AT THE POSTED SPEED LIMIT (70 MPH) IN THE CENTER LANE OF HIGHWAY 99 IN FRESNO CA. MY CRUISE CONTROL DISENGAGED (THE FIRST SIGN) AND I RESET IT. SEVERAL MINUTES LATER, THE ENGINE LOST POWER, THE GAUGES FAILED, AND THE EMERGENCY BRAKE CAME ON. LUCKILY I WAS ABLE TO BRING THE MOTORHOME TO A COMPLETE STOP, ALL THE WAY OFF THE ROAD. AS IT TURNS OUT, THE IGNITION SWITCH FAILED INTERNALLY, CAUSING EXCESSIVE RESISTANCE AND HEAT IN THE PINK POWER WIRE WHICH FEEDS THE CHASSIS PART OF THE VEHICLE. THE MAIN PROBLEM, BESIDES SUDDENLY LOOSING POWER, IS THAT THE EMERGENCY BRAKE COMES ON AUTOMATICALLY WHEN THEN VEHICLE IS PUT INTO PARK. WHEN THE IGNITION SWITCH FAILED, THE POWER TO THE EMERGENCY BRAKE FAILED, AND IT CAME ON, FULL FORCE, AT SEVENTY MILES AND HOUR!...