There are a few here in town. I'll see if I can get some ideas.
The molded pieces are the PITA. There was a guy that had made his own up in Jackson but I never paid too much attention to them. If memory serves, he cut the molded step and then built the slider under the straight line he cut. I'd say the bottom of the slider rail was pretty much the same height as the bottom of the molded step.
I'll call around to my Jackson contacts and see it anyone can locate it and snap some pics.
Forgive the crude mark up pic but from memory and 2 years ago.
J
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I thought of this as well, you'll probably never be able to see the cut lines with a slider sitting there. I think this is the practical way to go. I much rather not have to spend an extra $800 for whatever for the LC side moulding.