You would have to run the lines fairly close to the bottom of the tanks, and they could snag if you do any off roading. Or you could have one tank pump the fuel into the stock tank. Notice your gauge getting low, hit the switch, run a pump, then shut it off when the stock tank is full. Just don't forget or it will over fill the stock tank!!!
If you want to get really fancy, add a float switch to the stock tank that is triggered at a low and high point. Wire it to the other tanks pump, then when it gets to say 1/2 or 1/3, it fills the stock tank back up to 'full' automatically. Thing is, you would want a low cut out in the other tank as well, so when it runs out the pump isn't coming on and running dry.
If your going to go through all that trouble, just do the selector valve. Now on a deuce, you would also have to have a switch to control which pump you had running as well.