Knob runs into some plastic or rubber funnel, just tighten it until it feels right and align it.
If it's really sloppy, like inches wobbly when in gear, likely the shift linkage U joint.
Probably the most annoying part you'll run into is tapping out the 2 roll pins, especially with no lift. If you're gonna be working on the floor, it's a good idea to wear a face shield. Keeps dirt and hammers away.
This video is pretty complete on what you're planning to do.