I actually had a wooden version of this at one point as well, and I remember that the worst part was getting the cams glued into the right spots with the thing already assembled.
So I upgraded the original of this by changing the center rod with a square shaped rod, and changed all the circular holes to square holes. This way, the cams stay in place, and the whole thing is easier to put together, no glue needed. You may need to sand down the square rod a little bit.
You will still need the original files as well, I only changed the pieces that needed to fit the square rod. Though I also included a slightly longer post to make the tail twitch a little higher.