Need a little help for anyone who has a good set of parts manuals for All Datsuns. I found an NOS part, but it was not the correct part for my 1970 Z. Can anyone tell me the purpose and car model part # 25230-89903 is for? The part I was looking for is #25230-E4100 which is the rear window heater relay. #25230-89903 does not show up in the parts CD. Thanks for any input. Dan