From what I read you still have a surge after cleaning the carb. Possibly you have done the following but just in case did you?
1. Replace the needle seat. After market seats are often not as good as Tecumseh original replacement parts.
2. Check the orientation of the bowl. Lower bottom part with the dimple goes away from the float hinge.
3. Check the float to carb rim distance when upside down, I think 11/64. Using a drill of that size makes checking easy.
4. Dip the carb in solvent overnight. Makes a big difference versus a quick clean with aerosol carb spray.
5. Clean the small holes in the bowl nut with a very thin wire. Stripped tie wrap.
6. Run a small wire through the pipe running from bowl to throat. Put some slight bends in the wire so it lightly brushes the sides of the pipe.
7. Check the bowl for dregs broken off the gas line. If you find any disconnect the gas line at the carb and run lots of gas through shaking the tank to move dregs. Most tanks have a very fine filter inside the tank. The old metal gas shutoffs came with a fine filter. Some of these filters get rust holes from water.
8. Insure the air vent hole on the flat above the idle mix adjust is open. Spray carb cleaner into the port for the primer and through the cutout for the welch plug. You should see a flow out of the air vent.
9. Give a final high pressure air wash to all ports and holes or the same with carb spray.
10. Spray up into the fuel line at the carb and see what comes out by catching it in a clean cup.
11. Generally a surge after a tank dip cleaning is due to crud still in the gas line. Look in the gas tank and see if your screen is till good. Every tank I’ve ever looked into has dregs and the same for refill tanks. One way to get a good cleaning it to run a water hose into the gas tank to flush out dregs. Tilt the tank to suck up any remaining dregs with a hand suction pump or siphon. Stuff a cloth into the tank and switch it around with a screwdriver to get the last of the dregs and water out of there.