Martin,For example you could cut the base into individual chaired timbers, and stick them down one at a time on a curved template. A bit tedious, but not actually difficult. Slide the main-road stock rail (pre-curved) through them as you go to ensure they are correctly aligned with each other. Remove it when the glue is set to allow the switch blades and tie-bar to be inserted.
That takes me back a good decade or two. I used to use the SMP kits with the injection moulded bases and cut them into point timbers with the chairs attached. I seem to remember the chairs were a little under scale size.
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