Quick and easy way is get 3 barbed fittings the same size as the hoses.
1-Fuel supply
2-Return
3-vent
Disconnect the drivers side lines from the selector valve-switch combo. And using the Barbes, reconnect the lines to the hoses leading off the selector valve towards the engine. They are all different sizes so it's hard to mix them up.
To make this permanent and delete the whole passenger side tank, selector valve and tank selector switch, will be a little more involved. It's not hard, you will just have to pull the switch from the dash and connect the fuel pump power and sending units permanently to the driver's side tank. Now you have a switch hole for something else, lights, locker, fans,train horn, disco ball.....