Congratulations!
I never heard of a squirrel cage swift so I had to look it up. There are lots of links on Google and some of them may be plans. There are lots of pictures though so you may be able to figure it out if you can’t find any. I will say I don’t think there is a standard skein of yarn. The best thing would be some way to make the swift adjustable. Since it’s vertical you might be able to make the parts slide on a track then lock in place. Just throwing that out there.