Lots of washing up liquid in the rubber channels, start with transom boards rear edge, then put the leading edge of the front board in, join the boards with the H-section alu piece and then push the middle down and work the sides.
I have a really thin flat jimmy bar that I have taped up with insulation tape at the end so it doesn't damage the boards. I use this and strong fingers to work the rubber section. A friend usually helps.
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