Or it could be that the Hudson, when it's tuned right, still only turns an eighteen second quarter mile ET, and I'm used to driving something that's 8 seconds quicker.... Mine was not running at it's best, but the Hudson is still not a fast car, by any modern standards. Yeah, it was pretty hot in 1951, but look at the competition.
First things first, what is wrong with keeping the original Hydramatic? And if you could find a 1955 Cadillac hydramatic bell housing, then you could use any Cadillac engine from 1955-1963. Seems to me to be a much easier way of putting a Caddy engine in the Super Wasp! Obviously you will still need to weld some front engine mount brackets to the frame. But with the engine bolted up to the existing transmission, you will have longitudinal alignment and only need to place the front engine mount brackets. This, of course, is dependent on whether or not the V8 clears the firewall, steering shaft, etc.
I guess it's too late, but the 390 Cad will give you a lot more power -- and that car ain't a lightweight. I guess you could look it up, but I'd think the Cad wouldn't weigh that much more than the Hudson -- they didn't cutback on iron. And ditch the bumper guards. They're just clutter.