I've got mine mounted to the upper belt guard bolt which is a little farther back then the normal axel mount but not by much but if you install the mount upside down( or I should say a mount for the right side mounted on the left swingarm) it may make it low enough to get clearance for the bags.

If not maybe see if you can get a second plate and mount one to the bag itself with a quick disconnect for the lights.

 

Here's an idea ...

Make a bracket from a piece of angle iron kind of like the picture. The top goes inside the fender. Run the bolt that holds the turn signal through it. The license backing plate attaches with the 2 bots on the other face. If its the right length and angled right, the plate will sit right up against the back of the saddle bag. You could do it on either side of the bike and run it horizontal or vertical, whatever your state requires.

I borrowed the pic of the bike with the saddlebags you like to give you an idea of what I'm talking about.

Just an idea.

 

Not trying to be a ***** but those bags and that chopped fended look terrible. Bobbers are supposed to be minimalistic and those bags ruin it for me but I am a strong believer that it's your bike, do what you like. On that note, the Road6 custom side mounts are only held on by the axle nut, it can be removed in less than a minute. You don't have to worry about the axle moving while the nut is off becasue the adjusters hold it in place. You could use wing nuts to hold the plate on the mount so you could easily remove it and screw it to your bags in about 2 minutes. As far as the license plate light is concerned, ditch it. I have never had a light on my side mount. I was worried about getting a ticket until followed my brother at night and could not tell the light was missing. Not sure about where you live but CA license plates are highly reflective. My factory mount came with two small round red reflectors screws and wing nuts that hold the plate on, I reused them on the top two plate holes. That is enough for me, LEO would have to be a real bastard to pull someone over for that.