the a/c in my '73 88 will only operate on HIGH. i think i need a low range relay. got assistance at cadillac dealer. he gave me the #409560 which is a low range relay. upon finding a new one, the one on my car doesn't match. of course, this has stumped me. i'm going to post here a shot of my relay & a 409560. not sure what you call the prongs, but they are not the same. anybody have any ideas? thanks!!