[jmt455]

Jeremy,
Sounds like a classic case of worn or missing shift linkage bushings.

If they are missing or worn, replace the nylon pivot bushing, spring and thrust washer at the linkage pivot bracket (where the shifter rod pivots in the frame bracket).

Also, there should be a compliant (usually green) bushing at the connection between the shift column lever and the shifter rod, down low on the column in the engine compartment. Those bushings are usually broken, mushy or missing.

You'll never get the linkage to work properly if all of those components are not in good condition.

Also, follow the adjustment procedure exactly as described in the Service Manual; if you don't use the proper sequence, you'll be chasing your tail to get it to work properly with the Park/Neutral switch.