Although there is no instruction in the manual, there will be a hole in the original staircase, so fill it with plastic material.
Furthermore, the dent in the deck is a place to attach a bench. The etching instructions simply say “fill in”, but it’s more difficult to fill in than scraping. This time, I cut and installed a 0.3 mm plastic plate by matching the actual product.
It is in the state of filling the dent in the deck. Next, there is polishing of the deck, so let it dry sufficiently at this stage.