Yes, I read the response. So the 518 is a 727 with OD extension housing? If that is the case is there a number on the case I should look for from all the core transmissions laying on the ground at the local pick-n-pull? There have been a lot of transmissions made in the last twenty years and a lot of them look the same to the untrained eye. I don't pretend to be an expert. I want the simplest and strongest OD Chrysler Automatic that would not require additional electronic controls to operate. I have had painful experiences with Ford AOD transmissions (3 times in a Ford Expedition @ $3,000.00 a whack, finally rid of that POS) and I don't want a lock-up converter as that was the cause of at least one of the Ford failures.