Very low voltage at starter signal wire

1987 4runner with a 22re and 5 speed. Had a no crank, no start problem when I bought it. Previous owner had an automotive 40 amp relay in place of the original starter relay, but it wasn't wired correctly. I wired it up and it fired right up. I've been slowly working on this rig whenever I have time and it's always fired right up. Now, it won't crank over. Just like what it was doing when I acquired it about a month ago. I found factory starter relay and wired it in according to how I've seen it on this forum. Still nothing. New battery, alternator, and starter. I've redone the grounds. I tested the battery cable going to starter and it's at 12.8 volts, the smaller wire that connects to the starter isn't reading any volts, earlier today it was reading .002 volts on my multimeter but now it's at 0. I'm not good at electrical stuff so I need some help....thanks in advance for any suggestions, tips or advice.

 

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