I've made 3 of them, and never worried too much about the mix either. I put titebond III in a small Dixie cup with a few drops of water and it's been fine. Doesn't matter what it looks like when you get through (it's a mess) but I also think the water helps the wood be a bit more "flexible" - important when you're getting small, sharp-cornered pieces in a marginally bigger hole. My biggest challengs is my 55 year old eyeballs. They don't work like they used to! My kids think I'm a fvreak when I wear my Mageyes, but without those, these kits would be impossible for me. The kits can be tricky at first, but you get the hang of it quick enough. And call Ken if you need anything, he's the best to work with!
Good Luck,
Dale