fixite7,
There are some original Delco relays available on ebay. A 55/56 that uses the ring terminals for about $175 and a 57 up that uses spade terminals for about $120. I use the Bosch type relays in the wiring kits that I provide with rebuilt overdrive units. They work fine and most people don't want to spend that much for a relay. Similar story with KD switches, the Ford switches are reproduced and are about $30, NOS Delco switches are $200.
Fred
