I did the opposite. Wiring shouldn't be much of an issue. The fairing stay for the 1125 is wider than the firebolt. So you'll have to make some spacers or get ahold of kdfab and they can make you some brackets. You will probably have to do a little rewiring as the plugs are different, but they can be purchased online.
I would love to see photos of this conversion before I pull the trigger. I had a 1125R once and liked the extra wind protection and bright lights (no, I don't want HID's).