Hello there,Can anybody tell me where I should install a low pressure brake switch at? I am running a Corvette style master mounted below the cab. Disc on front, drums on rear. A 2 lb residual valve for front brakes and a 10 lb for rears. Then behind the rear valve I have an adjustable preportioning valve. I'm thinking it should be installed ahead of any of those inline valves. Can I get some thoughts from anyone? Thanks PS I have a Painless switch part #80174