First time builder, in the kit is 3" 9oz glass cloth for beefing up bottom, 14 feet long. What is the 18" piece for?
I think it’s for the leading edge of the stem. But a diagonal cut ribbon of the same size would conform better. I built a Tandem, not an Expedition, my advice might not be relevant. Enjoy your build!
I was going to guess stem as well. Nice of CLC to include them pre-cut. My kit did not have that.