lowfly, I tow a Seadoo behind the FW, I installed a wireless camera to keep an eye on it while towing, got it here:
LinkageI did much as you suggest, mounted the camera on the ladder, the x-mitter under the nose. The camera co. sold a plug-connected extension wire to get from the camera to the x-mitter at the front of the trailer. Possibly might fit yours. I wired to the parking lights, my preference, but it could have been any 12 volt source. I tied into the wiring for the TV plug.
Works great for me.
Tin Pusher's Guide To Successful RV'ing: "Don't get mad, don't get in a hurry"
2002 1500HD
2002 Wilderness 265H
1997 Seadoo GTI
1952 Wife;)