Smooth mouse wheel camera zoom using SpringArm

I am trying to implement your blueprint snippet with little success. All I am able to accomplish is setting the default SpringArm length, which is bound to the “min” value in the clamp. In other words, by default i am zoomed in and I cannot zoom out.

If you can help, I have some additional questions as well. One, does this need to be hooked up to the “Event Tick” with a gate or something? Also, is there a way to set the default Spring Arm Length that is not the min or max clamp value?
Thanks!