Yes even if the starter relay on the fender clicks it can be bad. The contacts can not be making contact. Image below.

But if your starter solenoid mounted on the starter clicks and it bench tests good then you have a ground or power cable problem from the battery to the starter.

Where does your big ground cable from the battery ground to?
If it is not the engine block then that is your problem.
The frame is not a good place to ground the battery as there is not a ground path from the frame to the engine block to carry the high current.



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