JUST TOOK OUT A 7 1/4 REAR END OUT REPLACED WITH A 8 INCH OUT OF SAME YEAR 68 MUSTANG. THE ONE I TOOK OUT APPEARS TO BE A POSI UNIT? SHOULD I STILL TOSS IT? PLUS I NEED A POSI UNIT FOR MY 8 INCH THE 7 4/1 TAG CODES ARE WCY R X AT THE TOP ON THE BOTTOM 2.83 7BD 9.03 THE X AND THE 7BD ARE IN DIFFERENT STAMPING??? I CONVERTED MY 4 LUG TO 5 WITH ALL NEW FRONT AND USED REAR EMAIL IS DANE.OH@NETZERO.NET IF YOU WANT TO EMAIL DIRECT I AM NOT GOOD ON COMPUTERS. THANK YOU I PICTURED MY 73 RAM AIR POWER WINDOW AC CAR {may sell?} PICTURE WONT LOAD TOO BIG IF INTERESTED SEND EMAIL ILL SEND PICTURES CAR IS 99 PERCENT DONE NOW