Not sure what might be the problem. Have you checked for any debris in the shifting mechanism between the shifter and the actual transmission?

I don't think the starter interlock switch could cause this unless it physically broke and the broken piece somehow is jammed where it shouldn't be... but this would be pretty rare.

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
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