I could only do a test that was safe in the kitchen...
Flooding might indicate a untight float valve. There is several details that is important to get a float valve in a DLX tight, as the needle is moving about much more than a common modern float valve assembly where the needle is guided way more precise. Most common mistake is to make the seat too wide and deep. The thinner the seat is, the easier it is for the valve needle to assume a position that will seal.
There is different ways but this is how I do it. First of all the needle tip cone must be pristine, sharp, smooth and shining. I set it up in a clamped down cordless drill, support the needle tip on a block of wood to steady the needle wobble. Set the cordless on slow speed. Shape the cone with a high speed Dremel with a dremel flexible Square Edge Rubberized Polishing Wheel. Be light on the hand! it is impregnated with abrasive and way effective! and polish it with a Dremel lump wheel. A tip for the rubber wheel is to center and square it by, with the dremel at speed, grind it against a spinning common grinding wheel.
Grind the bowl seat tower down flat with a Dremel flat ended grinding stone, until there is almost only a sharp edge left of the old seat, 1 mm seat is wide in my opinion. Even better if the thin new seat is convex so the needle can tilt a bit and still seal. A convex bowl seat is achieved by swinging the needle in the seat, with finger pressure, round and round in a circle for a fair bit of time. (a pen ink tube can extend the needle top) That will shape the seat well enough. Nothing coarser than a bit of cigarette ash should/might be used as grinding compound. Cigarette ash mixed with a little spit and crushed to a fine paste with the backside of a spoon or similar.
The carb is vibrating hash and violently during run...The float must never risk touch the bowl sides or carb center stem. The float fork is better not have too much slop on the shaft, the fork side play must not be too big, the valve ball must fit in the cup with not much up-and-down or side-to-side play. Too much up-and-down play there might risk starving the engine from gas as the valve can't lift high enough to let gas in fast enough.
After a while (one summer) the float action has pounded the needle and seat deeper so a readjustment of the float level might be needed. A light float wear less on the seat than a heavy float.
