BATTERY TERMINALS NOT GETTING CONNECTION,
BAD CONNECTION AT THE END OF GROUND CABLE TO MOTOR,(BE SURE THE CABLE IS CONNECTED TO A SOLID PART OF THE ENGINE AND NOT TO A BRACKETT.
BAD CONNECTION AT THE POSITIVE CABLE AT THE BATTERY OR STARTER.
CHECK FUSIBLE LINKS AT STARTER SOLENOID,PULL ON THEM ONE AT ATIME AND SEE IF THEY STRETCH,IF THEY DO,ITS BAD.
IT WILL NOT BE THE IGNITION SWITCH ,ONLY PART OFTHE ELECTRICAL SYSTEM RUNS THRU THIS.
REMOVE YOUR BATTERY AND HAVE YOUR BATTERY TESTED,NEW PARTS COME DEFECTIVE TOO.(TESTED BY A REPAIR SHOP OR BATTERY CO.) (EXPERINCED TECH.)