I put mine between the master cylinder and the stock prop valve. It works fine, but the in-dash brake light came on. The problem is the reduced pressure tricks the stock prop valve into thinking the master cylinder is bad. So I disconnected the wire at the valve.
Cut open the line coming our odds the factory distribution valve that is going to the rear axle. The new prop valve will go in that line and limit the amount of fluid going to the rear brakes when adjusted.
I mounted mine in the line going back to the rear brakes. It's right under the driver's side door so that I can reach under and adjust it while I'm still sitting in the car. It seems to be working great so far!
just install it between the master cylinder port that feeds the rear brakes.
There is no need to cut the factory brake lines, just need a short section of steel 1/8 tube with fittings on each end and the proper adapter fittings if needed.
I mounted mine in the line going back to the rear brakes. It's right under the driver's side door so that I can reach under and adjust it while I'm still sitting in the car. It seems to be working great so far!