jparker66:
I've had a similar problem as yours and about the same setup. After fiddling around with it for about 8 years total and calling the setup many names, I finally did what you're thinking of doing by adding two separate valves and two separate connections and have had zero problems since and it's been two years now. What I gained by doing this was that the valves were now located out towards the side of the vehicle so that if I needed to lubricate them or clear any debris that was stuck between the seals they were now very accessible. Also replacement of the valves, if ever necessary, would be a cinch. On a side note, I figured out too late why my valves were so very hard to operate. It was because I unwittingly was using a petroleum based grease on them which causes the rubber seals to swell and drag against the blades. If you make this conversion I'm sure you'll be very pleased with the results. I sure am!