Dearly Beloved....as best as I can remember, heater cores that leak don't care if they are part of the a/c program or not. Correct? Part number 2521-268 for Chrysler cars in 1966 only heat water when asked or don't if the control valve is closed. Anybody have a part number from any source to replace a leaker or must the leaking offender be removed from the car and taken to a good a/c guy that could measure it's geometry and find a generic replacement?