This would appear to be happening. Telltale drips on the exhaust manifold below certain carb body plugs I’ve never before removed indicate leakage. See the arrows. Also, the entire carb body has a rather “wet” appearance that I don’t recall it having on prior rebuilds. I see what looks like seepage happening at cast joints

As Dan said, those aren't joints, they're just seams.

And you will observe that the drips are forming on the lowest points of the body.

From your photo, it also looks like the airhorn gasket itself is dry, which, if true almost rules it out as the source.

You fuel inlet / needle seat washer looks very wet though. And looks to me like it may be doubled-up.
If it is slowly oozing fuel, the fuel can crawl along the surface of the carburetor, especially along ledges like those casting seams, and cling as it runs down to the lowest point(s).

I would check the tightness there, and then re-check your float level.

More I think on it, more I suspect your float valve is making a pest of itself. That "Daytona Float Valve" they claim is so much better than a regular ol' normal ol' boring ol' inlet needle and seat, that's a copycat of the old Tomco "Duro-7" design, and — assuming it was a good design in the first place — something might've got lost in translation. I can think of a few ways a not-quite-faithful copy would cause problems such as you're having.

Too, and secondarily, I've never liked those red fibre inlet fitting gaskets. The rubber-coated aluminum ones seem to do a better job of keeping things dry. Might wanna sigh, grumble, and fetch a kit from Jon Hardgrove at TheCarburetorShop.com . It'll have the regular kind of inlet needle/seat, and together with careful float readjustment will likely solve all or most of the problem(s).

As to the carb body plugs: kinda stands to reason that plugs in place for decades' worth of thermal cycles, made of a different metal than the carb body, will've had time to become less than totally leakproof. I might apply a smart rap to each one via a pin punch, with the carb firmly installed.

That's a Holley-type design which works well on certain Holley carburetors. It does not belong in your Carter carburetor, where its side-discharge configuration will tend to make gasoline want to exit the carb through the bowl vent…in exchange for zero benefit.

So anymore, I'm inclined to file magic carburetor float valves right along with magic spark plugs, under N for Nope.

Big thanks to Dan Stern for the help locating the correct rubber-coated washers that are now keeping the fuel inlet dry

And also for the advice about the needle/seat situation. Sourced a new (original design) needle/seat inlet and already things seem drier than they ever have been.

there were nearly invisible, gummy deposits clogging the inside of the accelerator pump jet. I had to get out a sewing needle to help clear the passages. Once clean, a pump test with fuel in the bowl finally resulted in a relatively light spray of fuel through the jet into the carb throat.

sometimes the pump sticks. You'll work the throttle linkage and the pump will plunge down slowly, if at all.

I have reused my old pump spring many times because it seems tapered correctly from narrow at the plunger end, to wider at the top end to mate with the metal 'cup' that seals the pump vent hole.

The new accelerator pump springs that come in the Daytona kits do not taper at all. Their coil is wound too tightly so the end of the spring that rests inside the rim of that metal cup doesn't sit around the edges of the cup correctly to press it firmly up against the inside of the airhorn; all the spring wants to do is poke through the center hole of that cup seal.

What's 'relatively light' mean here?