I've run the same mix for years now in multiple trucks. I mix 8 oz. of Power Service (white bottle in winter, grey bottle the rest of the year) plus 16 oz. TCW3 2-Stroke oil with every fill-up. Those amounts are calibrated for 25 gallons, but I don't worry if I'm only putting in 19 or filling with 30, close enough. I've read a lot of info over the past 8 or so years, and I still think this mix makes sense.
I make this mix in 3 or 4 quart bottles and keep them in the truck. That way no measuring and only one bottle to pour in at the pump.