Mike,
You bet! Easy as can be -- go to aux2, assign ch 6 to VRD (left slider). Go to FLPTRM and make it as high as you need to to get your maximum up and down spoileron/flaperon desired (you may not want a full 100%).

now do a mix: ch 6 to ch 6 -100%, link ON, on/off on whatever switch you select. This will turn off the slider whenever the switch is in the on position.