"...Is there a crossover underneath the bike from one board to the other?…"
No….there is not.
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Because I decided I wanted to use the OEM brake pedal in association with the FXRP floor boards it took some cutting and grinding….please note that most FXR owners do not have a "chrome" brake pedal on their FXR's. FXR3 and FXR4 bikes were "optioned" with a chrome brake pedal….cutting "chrome" can be a dicey experience since you might actually cause the "chrome" to "flake off" so if anyone decides to cut off their brake pedal and they have a chrome one you do so at your own risk. I actually own several brake pedals as I wasn't sure how this was going to come out….so I wanted a couple of back up plans. I found a FXR3 and FXR4 chrome brake pedal and have it nicely stored away if for some reason i ever tire of the floor boards and want to simply go back to an OEM brake pedal, however to tell you the truth I like the "smaller" version of this brake pedal now that I have cut it down. I also own another aluminum brake pedal that I found just in case this did not work out well.
I am here to tell you with some time and a floor grinder, and or a 4 1/2" grinder with a cutting wheel and a wire brush you can end up with a very nice finish…aluminum is very forgiving for sure….there is nothing to be gained by cutting off more than I actually did.
And by the way there is enough adjustment with the brake pedal height adjustment to make it work in conjunction with the height of the floor board….Also note that I am running a Supertrapp 2-1 Supermeg set up for as softail application and it works on the FXR2 as well as the FXR3 and the FXR4 or for that matter any FXR with enough effort….and so the modification to the use of the floorboards will work with that pipe as well.