Being over weight by about 2000# on GCWR you will definitely benefit from an EB.
I have a US Gear 'D-Celerator' EB.
It is as simple as they get. Installs in exhaust just after turbo elbow.
Uses 12V DC thru a HD solenoid to close 4" butterfly ,,,, has a 2" modulating bypass butterfly to control backpressure.
Electronic control box installs under dash with an ON/OFF push button that is sticky taped to any spot on dash with a paddle switch on accelerator pedal.
Turn ON (activates control box) and when you lift foot off accelerator pedal paddle switch makes up....EB closes
With Tow/Haul mode ON and EB engaged it will hold 45-50 mph on steep grade
Have read about some problems with it......bushing seizing, EB sticking closed but in 8 yrs. have not had ANY issues. I think some of those issues are do to owners NOT allowing EB to self test.
When you turn ignition ON the EB will auto cycle .... this helps keep butterfly valve from sooting up and keeps bushing/shaft movement free.
If you 'blip' the accelerator pedal when you turn ignition ON it will cancel the auto cycle/self test. Do that a lot and soot can build up.
I let mine do the auto cycle everytime.
Plus I have EB ON a lot..whether towing or not so it gets used routinely.