you have to swap the sliders for a touring type that has the dual disc slider....
then you have to use the HD (or aftermarket but the HD ones work the best and are fairly inexpensive) FatBoy fender adapters...
the biggest part is your wheel... it has to be able to accept the dual brake rotors... most if not all FatBoy wheels do not do this...
as for the axle size .....
you can get a wheel with the correct axle size or you can just change out the bearings.. the sealed bearings all have the same OD (outside diameter) but the ID (inside diameter) is different.. so you can put whichever size bearing you need to fit your axle..
but if you are going to go that far you might as well use the HD brembo's..
all the same except you add brembo rotors and calipers..
easy as pie...
If it is too Loud, Ride Faster.
To be old and wise,
you must first be young and stupid......
Here's to old and stupid....
Screw it, Glue it, or Nail it..
SE Welded/Balanced Flywheel
CP Hi-Comp Pistons
Andrews 54G Gear Drive Cams
S&S Hi-Lift Valve Springs
Baisley SuperSTock Heads
V&H True Dual Headers
Bassani Slip-on Mufflers
T-Max Ignition System
Feuling Oil Pump
Custom Feuling Cam Plate