"Normally", when the low fuel light comes on you have about one (maybe 1 1/2)gallons left in the tank. I've read where some folks have added aux tanks to their Wing. Most have installed them on the back seat. So unless you do only solo riding, it's not an option for you, unless your SO is willing to sit on top of a tank of gas...
Years ago my Dad built his own trailer with a small tank and transfer pump on the front.
I keep forgetting to stick the tank when it shows empty on the guage. Don't know if the light works or not. I'm not into walking down the road with a gas can.
My 97 when the light came on I had 52 miles left at 55MPH. Go to Tour Tank. Com they make great barrell tanks put one on the wifes Yamaha VStar 1100 had it on her VTX as well 3.5 Gal tank fits nicely on the back seat if you have no passenger