I don't remember if the lower side is the switched side or not, but usually when I see this scenario it's going to be the ignition and accessory relay. It's located upside down on the right kick panel up above the fuse block. If you ever get a windshield leak, it will leak water right into the relay and short it out. You'll have to pull the glove box to get to it.
Z man of Washington
1978 black pearl show car-retired, I bought it new
1983 zx turbo daily driver, modified, 3rd owner
1970 240 #23 being restored
1970 240 #638 driver
1973 240 roadster being built
about 70+ other z's & zx's
57 Chev Sedan Delivery
67 Jag E type
2 620 Datsun Trucks
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