i had a '79 240 stick that needed a new starter or so i thought. i can't help you with the procedure, but here is my experience from many moons ago......

.....went to the dealer and paid 400 bucks for the 100 pound starter. 4 bucks a pound. installed it and it was grinding within a week. took the car to the dealer, replaced the ring gear and bought another starter and it was also grinding within a week. three starters, ring gear, lots a labor, towing, batteries with the bottom sucked out of them, a wrecker driver that cross connected a battery and blew the caps off of it. thousands.

i ended up tapping into the key circuit and mounted a voltmeter to the windshield. every time i hit a bump the starter would engage while the engine was running.

i spent thousands over a 30 part because of a simple mis-diagnosis. i'm older and smarter now. i just say 'fix it.'

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