1989 Ford Bronco Brake Line Routing Sketch - Master Cylinder & Proportioning Valve

This is a hand-drawn pencil sketch (schematic) of a vehicle brake hydraulic line routing, uploaded to a 1989 Ford Bronco gallery. The drawing shows a master cylinder (labeled 'Master cylinder') mounted against what appears to be the firewall/booster, with brake lines running from its ports to a rectangular valve block (apparently a proportioning/combination valve, marked with up and down arrows at two ports). From the valve, lines route to the driver-side caliper (labeled 'caliper driver side'), the passenger-side caliper (labeled 'caliper pass. side'), and to fittings at the top of the sketch labeled 'To Rear' and 'from rear', indicating the rear brake circuit connections. A large arrow points to one line junction with the handwritten question 'Is this backwards?', suggesting the owner drew this to ask the community whether their brake line routing (likely at the rear-circuit tee/junction or valve ports) is connected in reverse. There are no part numbers, torque specs, year/model statements, or dimensions in the document—it is purely a routing question sketch. Readers can learn the owner's as-installed brake plumbing layout and the specific connection being questioned.