Having survived some pretty hairy driving emergencies while pulling a trailer, let me offer a suggestion- - - - -if you can figure out a way to mount your trailer brake controller in a position where you can manipulate the manual control with your knee, it lets you keep both hands on the wheel when reacting to an emergency. I usually fabricate a small extension to the manual button and mount the controller to the dash or steering column near my left knee. It's saved my bacon a couple of times!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!