With the DD kit you snip the line at the frame rail right next to the tank. Then run a short piece of the supplied line to the 4601 which is mounted on the inboard side of the frame at approximately where the front of the fuel tank is. The kit includes a custom little wire loom that plugs in to the same plug your old lift pump did. You then take some more of the supplied line and run it up to where the stock lift pump is. That gets pulled and you put a custom piece designed to fit where the lift pump was with an AN fitting and attach your hose coming from the pump. At the bottom of the filter you pull that banjo and the one on the cp3 and that line is replaced with another piece of the supplied hose and AN fittings. If you have a fuel pressure gauge you are likely using one of those points for your sender. I went down to NAPA and got a tee and some fittings and installed my sender in between the fuel filter and the cp3. Its been a while since I installed mine and I might of forgot something but thats pretty much all there is to it. Its an easy install. Only tools the average guy might not have would be an inch lb torque wrench and its easier to drill the holes for the pump mounting bracket with a right angle drill. That sucker is loud on a 3g. The three sounds you hear in my cab are the engine sound, exhaust sound and the fuel pump and all are about equal. Mine now runs at 13 to 15 in normal driving around and pulls down to 6 to 8 at max flog. Its a good kit that is well thought out.
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