the pic of where the click comes from looks to be the battery isolator.? ? ?is the trans manual?? could be a clutch safety switch, or as stated? the starter solenoid is not getting a ground which is through the brushes. if they are worn, tapping with a hammer will sometimes shake the brushes into contact with the commutator and voila? ?starter works.? ?if this is the case you prob won't get another go at it.? time for a starter
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