I took the BreakAway throttle lock off my old bike and installed in on the Rocket.
The brake lever on the Rocket is much thicker and did quite fit with the brake release. So I just adjusted / set it out of the way. I only use the thumb lock anyway, so it wasn't a issue.
I really don't care for true cruise control. I only need to lock the throttle for a few moments to stretch my arm / hands. Then it's back on the throttle. Works for me.