This is the correct kit to rebuild the landing gear emergency extension valve on a 1978 PA32RT-300T airplane. Found that the easiest way to do it is to disconnect the linkage, and micro-switch, and pull the bellows and valve assembly together. You have to remove the aft t-fitting to get the valve out. The o-ring on the non-linkage side goes on pretty easy, but the second o-ring on the linkage side of the shaft is pretty difficult to put on. Its a tiny o-ring that goes over a 1/4 inch shaft. I would order a few extra MS28775-006 o-rings so that when you shoot the first one into the ether and lose it, and then break the second one, youll have enough to finish the job. I threaded a piece of safety wire through the hole on the shaft, then put the safety wire through the o-ring to keep it contained, then stretched it up and and over the shaft. Not easy, but did work. The only other piece of the kit youll need is the PPSQ3 end fitting gasket and more an380-2-2 cotter pins. After the rebuild, the gear stayed up, and the pump stopped short-cycling. My first thought was that the pump needed to be overhauled, but after thinking about it, glad I decided to overhaul the dump valve first. Saved a $3,200 overhaul, which wouldnt have solved the problem. Good luck!