The reason none of it fits the magnum is the bag fillers. Technically speaking you can use the Lock and ride stuff for the XC/XR as the mounting points are the same, but you will have to either notch out the bag fillers, or remove them completely to allow it.
I bought the bag fillers for my XR, and notched them to allow me to use the Kuryakyn Multi purpose Backrest.
2012 Cross Roads renamed "The High Road"
Barnett Scorpion Full Clutch, HE Clutch Cable
Blacked out Chrome trim pieces
Kuryakyn Tail light trim, Sabretooth Brake lights, Multi Backrest, Driving Light Switch (Garage opener)
Boss Audio MCBK400 600W stereo
Victory HardBall Mirrors and Mini-Apes, Big Mouth Exhaust Tips
Vicbaggers Ez-Clutch, Lay Down License plate bracket
Victory Beacon LED Headlight
LSL Adjustable Levers
Custom LED Driving lights
10' of LED RGB Strip Installed