Use a screwdriver or simiiar, remove the neutral button by prying/pulling it out and underneath is a bolt. Pull the bolt, pull the upper and lower covers, then you will find the bolts holding to the plywood. Fairly straight forward once you get the push button out. The button is plastic, has a barb on it which holds it in place.
Super Guys. Thanks so much. This is from a donor boat that I owned for 15 years and works wonderful. I could not see letting it go to the landfill. I wasn't sure, so I cut the trim plywood with a saw until I had more time.
Although the project boat "Sarah Lee" has the same control, it has not been tested. So I removed every system from the boat so now I have two of everything except the engine block. I have a 5 gallon bucket of ALL the hardware even. LOL
I did have room for my suitcase in the passenger seat.....