Just checking the resistance with an ohm meter won't tell the whole truth. You need to have a load applied to see what it does with amp draw. Someone posted previously how you need to do that. Or just go to a parts house and buy a $10 negative cable for a temporary check.I took the negative battery cable out of the car. Layed it on a bench and set my ohm meter 0. Took the two probes and touched each end of the cable and the result was 0 ohms of resistance? I did the same thing with the attached radiator support ground wire which is part of the negative battery cable in 1970. It also reads 0 ohms of resistance? So I am trying hard to figure out where the high resistance is? I have removed the engine block bolt in the front of the head and the captured nut in the radiator support was also sanded clean, even though both were nice and clean. So I am actually doing what people here are talking about, but not getting anywhere?