Tune it at the launch ramp, on the trailer. Bullhead Comm Park is kinda shallow and murky, Riverside casino is deeper and good clear water. Just do it on an 'off' day, like tomorrow

Then theres always Lake Mohave.
I also static time every motor I've ever built, or replaced or removed the dizzy. Set your balancer on 10* (or your initial timing), set dizzy to fire at that point.
If ya need a hand, I'm local.
Daniel