Rear disc proportioning valve

J.B. said
The valve will be bolted up keeping it from moving. Will the flexible hose be ok since it secures to a fixed hard line?

IMHO really bad idea.

The hard line is going to vibrate and move due to the constant movement of the rear axle and metal fatigue will brake it is a very short time.

best is to mount the valve where the factory had it. they mount stuff the way they do due to years of engineering and knowledge