What's the terminal voltage of the battery- - - -measured at the posts, not the cable clamps? On a fully charged battery it should be 12.6 volts or slightly more. Now, try to operate the starter while someone monitors the battery post voltage. If it doesn't change, or only drops slightly, find the bad connection or open circuit from the battery to the starter and back along the ground circuit.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!