Did you look over this and read it.
http://www.pacificp.com/pdf/Dual_Fueler_LBZ-LMM_65-10.pdf
You need to remove the race valve or your fprv from the rear of the driver side rail and replace it with the new feed inlet. Take and install the race valve or the fprv into the gold looking block that mounts to the valve cover. The little horse shoe looking hose is on the driver side rail just in from of were the race valve or your fprv was and loops up from the rail to the return fuel line. Once the new feel inlet is in the rail you no longer need anything on the rail side of the return or you can leave the horse shoe looking hose there if your using a race valve in the gold block if you are using a factory fprv in the gold block you will need to run the new longer pop of fuel return line fron the nipple on the gold block to the return above the driver side rail in the rear. then on the pass side you need to cut and install the t fitting into the fuel supply coming out of the filter head just a few eachs out that will be the fuel supply for the 2nd cp3. then you will take the 5/16 line with the T fitting and cut and install that on the return side of the stock cp3 pump. Then all your left with is wiring and mounting the extra pulley and pump braket its not that bad just read and lay out everything and get all the hoses togther with the fittings to make it easier. The nut should be fine should also be a washer with it if I recall its smaller at the end of the shaft once the pulley is on and the washer and you get the nut up on there the shaft gets fatter tq to 52ftlbs.