Tranny and diff fluid change is a must with that mileage. I swapped mine at 25K and the shifting difference was big.
Go with Redline D4-ATF, and 75W90 gear oil, which already has the frition modifier. You won't be sorry.
Go buy a torx bit for a ratchet drive. Auto parts store.
The shift knob sounds like it's missing the wedge shaped pin. I think some call it a devil pin/clip It can be a challenge to remove it.
Either get a replacement pin from the dealer, use a lock nut from below on the shifter shaft, or get an aftermarket shifter.