Holley 1945 carb direct replacement for a slant six? Ideas?

The carburetor you're asking for (not by name) is a new old stock, never "remanufactured" Carter BBS for a 1974 Dodge Truck, that is BBS № 7044 or 7045. Looks like this (Photo I · Photo II. Second preference if you're sticking with a 1bbl would be a '71 198 BBS, № 4955 or 4956, though pre-'74 carbs have no built-in throttle return spring, so you'd need to add a second one to your existing external spring. You'd also, with either kind of BBS, need to put on a different choke thermostat. Kind of tied for second-preference would be a new(!) '76ish to '78ish 1945, thoughtfully jetted. Lotsa luck finding any of these; the new-carb supply has really dried up. I'd suggest getting in touch with Jon at thecarburetorshop.com , but his website seems to have gone all the way dark; I hope he's okeh.

Better overall result (also more work and cost): a Super Six intake manifold and one of these.