The most difficult repair job on any Kaiser that I've found is servicing the speedometer on a 54K. When new, the wiring was soft and pliable, there was no windshield in the car, and the seats weren't installed when the dash was put in place. Now...50+ years later, working on one can be a chore. One needs an arm hinged in 4 places to do the job right, but without that, here's the best way to tackle the job.
First, remove the negative battery connection...then...
1. Remove the center cap that covers the gearshift mechanism.
2. Reach in and remove the mounting screws that hold the speedometer in place.
3. Put some masking tape all around the upper dash half at the opening where the speedo sits. You'll thank me later for this step.
4. Gently pull the speedo down and forward so that the top of the speedo is tilted outward.
5. Reach in and remove the cable from the rear of the speedo. I used a long pair of needlenose pliers to accomplish the task.
6. Look for the connector that attaches all of the wiring to the main harness. Gently pry it apart.
7. Sometimes, if you wiggle and jiggle the speedo head, it'll come out. Sometimes, depending upon how the wiring harness was installed, it's stuck. If that happens, you may need to drop the lower dash half down a bit to make room for the harness. Do that by removing all of the screws and bolts that hold it in place. You will only be able to move it an inch or so...that should be all you need.
8. Pull the head free of the dash. If you forgot the tape in step three, you now have a scratched instrument cluster opening.
By the way, the dash lights on a 54 sucked when new. Your best bet is to jump the rheostat on the light switch so that the dash lights are on the full brightness any time the parking or headlights are on. Over the years, the reflective material on the instrument face gets dusty and also dries up and falls off, reducing their effectiveness.
One more thing, almost every 54 that I've ever owned (10 or more) all of them had the same problem where the top of the cluster sits low in the dash frame.