The Avenir is boxer ,the clipbrite has nice curves,both have 7 leds the Avenir seems brigher,but the clipbrite might need new batterys i used the one supplied.both have the same handlebar mounted switch and brake light sensor,the brake sensor is mounted on your brake inner cable and put in a position where a small movement of the inner cable the sensor hits a cable stop and presses the switch,i would not set it to close as you might bottom out the sensoe and break the sensor. i am not sure about your mounting problems the wire that goes to the unit should be on the bottom(speaker wire) there is a screw in the back side that your bracket will mount onto,this screw is black so its easy to miss,its is also inside a little square resess that when your mount is installed it keeps it from rotating,the mount clamps around your seat post, i mounted mine on a bracket i made that also holds my side flashers,let me know if you need any help, (one day i will learn to post photos)