Have the same problem with my 2000, 242. I searched high and low for a replacement but didn't find any. I took off the rails (they mount from underneath so you have to remove the base from the floor of the boat) once off I was able to clean, straighten, and lube the slides, then made some pieces out of flat stock aluminum to replace the bent pieces that join the top and bottom slides together. The biggest problem is when people slide across the seat, it bends the pieces that that hold the slides together. Using some aluminum angle pieces I was able to stop the side to side movement. It's not like new, but it's much better than it was.
I appreciate your input. I may have to do this. I'd be interested in knowing how you braced it. Some of my metal parts are broken. Grew boats had a similar seat and used wooden rails, and they never broke. I may have to look to that as a solution as well. What a poor piece of engineering that mount was.
I have the same boat and a similar issue. Sorry i dont have a solution for you but just wanted to let you know that i feel you pain as my slider is awful as well.
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