Vacuum Pump Questions?

Don't scavenge tubes do basically the same thing for a whole lot less money?

I removed a set of scavenge tubes for the vacuum pump and thats where I saw the 2 tenths...

You can see in the valve covers the vacuum breaker and inlet to the vacuum pump. The inlet valve cover has a piece of aluminum epoxied across the width and length of the valve cover just above the rockers to keep from sucking engine oil. I'm turning the pump 1 to 1.