I wrote this for somebody new to gas the other day. Reprinting here FYI.
If you have the patience to play with that a bit to do it correctly, you are in for a very pleasant surprise regarding what is possible regarding low speed throttle control. The plan is to spread that first half of the throttle arm travel across a much wider amount of stick travel. This should allow you to easily pick up or drop just 100 rpm if you want, at speeds from an idle to half throttle. To do well with the plane you have, you're going to need that kind of control.

A lot of guys will set this up with a throttle curve. Setting it up kinda like 10/20/30/50 or 60/100 for a 5 step. Point is you're really spreading out the first half of the throttle arm travel. A butterfly type carb (on ANYTHING) is pretty much all in at about 60% open. There's very little left on the table as the carb opens fully beyond that.

You can also do this same thing mechanically. Check out the drawing below. In practice, if you follow it as illustrated, you really don't have enough control down low, like for setting your idle speed. The illustration is done the way it is to help make the point. You'll find if you start at something closer to that shown in the second step, you'll still have plenty of the differential you need, AND have good control over your idle speed.

2 notes. First, with a throttle curve only (electronic) setup, you don't have anywhere near the servo resolution you have with the mechanical setup. Second, a lot of guys, myself included are absolutely anal about good throttle response. For the best possible, you start with the mechanical setup, then trim as necessary with a throttle curve. That will leave you with the absolute best of both worlds!