I was thinking about adding 15 to 20 gal fuel tank to my rooftop tent trailer. I would have a pump and quick disconnect that i would connect to my 1999 Toyota Tacoma so i can flip a switch in cab fill main tank up while driving. This would allow me to fill up every 400 miles or more when pulling trailer instead of every 200 miles. I could not find anything with google search with aux tank and trailer that can fill while driving. Looking to see if this would be safety problem or illegal. any suggestions or problems you see with this are welcome.