You might be able to create a bunch of Groups in the ARR for specific light forces. Only issues with that is you will need to manually select which one you want, and can't just have it send the nearest one.
bummer using the ARR hotkey doesn't designate a pumper tanker singly to use as the lightforce enigne. thats the way I been doing it for the last year along with the taskforce key. I was just trying to see if there were other routes others have tried. to do a true lightforce in game its more of a confusing task locating the correct unit then dispatching it. maybe one day the devs might come up with an extra selection for pumper tankers in the ARR...