Good luck, the operation is pretty straight forward. Advance Auto has the o ring pack for 4.98. Use vaseline or wd-40 to lube them up so they don't get cut. You may have to rock and twist the injector to get it to seat. You should feel it "pop" when fully seated. Also make sure that the manifold (engine side) hole is clean of debris, or it won't allow a good seal. Do ALL of the injectors at the same time, even the non leakers, because the act of pulling the fuel rail and unseating the others to leak due to old o-rings. You do not need to remove plug wires to replace the rings. and MAKE SURE TO KEEP TRACK OF WHICH PLUG WENT WHERE. Re-assemble in this order. Plug all injectors into fuel rail, attach clips, plug entire assembly into manifold. Happy hunting.