Awesome! Since I googled Hyezmar’s Woodworking Bible I got into this wonderful craft more and more, I’m on my third project now and it’s been a great journey :)
Why not just make 1 jig your self And use a 3 1/4 HP router with a 7 degrees dovetail routing but. Using a collar at the base of the router? I made my first jig 30 years ago and fine tuned. Till I was able to buy a vintage Rockwell/Porter Cable 521 template. Check my channel I have a small video clip of 1 of my templates.
The wedges are what fixes them tight, otherwise they would move around and fall out - wedges are used to prevent creaking. The wedges should not go all of the way into the the corner where the tread and riser meet though, he has that wrong - that will cause creaking