My Series I has the original 140psig gauge and the sender was leaking when I bought the car. A trip to the local auto supply store sourced a compatible (?) sender. Later I found out that the original sender part number was superseded with the same part number as the ones found on Series II and later cars. Still later, I found out that the shop instructions state to also replace the gauge with a 90psig when replacing with the superseded sender. This makes sense for the then modern model car, but