When you set up your CVT and gearing, start counting the ratio from the output sprocket of the CVT and set it up as if it were a single speed. If you can align the output sprocket with the hub sprocket you can probably get away without using another JS. You're probably gonna push about 8-9hp there, so I think you can safely run a tall ratio like 6:1. On 26" tires, and the CVT upshifted to 1:1, your speed at 4000rpm will be 50mph. If you decide to run CVT only I think you can send those expensive go-fast parts back to AGK and save yourself a few hundred bucks.
No point in going faster. you'll realize this when you hit your first pothole at 50mph, spine begging for mercy from those skinny bike tires and saddle springs
or.. keep the go fast parts.. and forget the CVT.. it eats power.. more so as the belt wears. I tried numerous transmissions until I found what I liked on my bike.. with only 4, maybe 4.5hp I achieved 50+ with a 2-speed auto and 7.7 top gear. prior to building a 2-speed I had chosen a single speed over the CVT.. the difference was about 15mph!!
build is looking good, best of luck and can't wait to see it done.