Probably be better off with a reman starter, IMHO

There have been some ignition switch problems associated with that style of switch, so that's a possiblity.
I'd try to rig it up so the next time it fails, you know if youre getting a crank signal (circuit 50) or not, that'd help with the diagnosis alot. Also possibly the shift linkage bushings, you can test by holding the brake pedal and bringing the shifter back to neutral while holding the key to "start".

Gilly

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