You can get the kits from ********AZ. They have the best price. It is a Royze kit that will have extra gaskets for different versions of the 35/40 INAT carb. Make sure to get the kit with the secondary diaphagm. Completely disassemble one carb at a time so you'll have on to look at. Soak the three parts of the body in laquer thinner for a couple of days then blow out all of the circuits. Check each part for flatness. The top especially can be bent (most people think it is warped from heat, but is quite malleable and will bend if the screw in the center for the air cleaner is tightened too much). Put it on a flat surface on a piece of 220 grit sandpaper and sand it enough to see if the surface is flat. If it is really out you can flatten it in a vise or with a small hammer on a flat surface. Make sure to get all of the jets and check valves back in the right holes. The primary and secondary have different orifices. Get the bench adjustments right and then all you have to do is synchronise them. Be sure to adjust the valves and set the timing before you try to adjust the carbs or they will never be right. These are great carbs. You will have people say to ditch them for Webers, but when set up right the Zeniths are superior. Good luck.