If your truck has a stock differential, frame and etc. If your brake line plumbing is original, You can take that Part Number to the bank.
There is a "T" that is clipped/bolted onto a bracket on the axle tube. That T allows for a left and right hard line to wheel cylinders. The hose goes from that T to a bracket on the frame. On that bracket, the main brake line coming from the front is attached to the hose. I'm sure you know all this. Never hurts to be sure.
If you or someone has changed brake line routing or geometry, I have no info. You will then have to find a hose used on some other truck that has the correct end threads and the length you need.
The flex you need is how much travel there is as axle extends away from frame. (in a pot hole). Jack up frame, let axle sag in midair (tires off the ground). Then you will know if hose will be long enough.
Be sure to buy it at O'Reilly's so you can take it back. Don't order it online until you are sure.
