CHANGED OVER MY '70 MACH 1 FROM AUTO TO 4-SPEED. PURCHASED USED HURST SHIFTER AT SWAP MEET. AFTER INSTALLING & TESTING IT, THERE IS NO LOCKOUT FOR REVERSE. SHIFTER WILL EASILY GO INTO REVERSE IF DOWNSHIFTING FROM ANY FORWARD GEARS. WHAT EXACTLY IS THE PROBLEM? DOES IT NEED A FULL REBUILD, OR IS THERE AN ADJUSTMENT? TANX. CENTER ADJUSTMENT IS CORRECT, NO TROUBLE GOING INTO ANY GEAR, BUT THERE IS NO PRESSURE GOING INTO REVERSE.