Decades ago, I worked as a repair tech on Tektronix oscilloscopes. The general procedure for ALL equipment coming from the shop was to put it in the wash rack. The wash rack was a metal box/sink with a lazy susan inside and the exact same kind of sprayer that you typically see in self-serve car washes. We’d take off the side panels and hose the equipment down with soap and water. And then, we’d put it into the dryers, which were enclosed cabinets kept at about 120 degrees. They’d be in there for a couple of days. The only concern with the electronics was there were some large can transformers that could contain a pool of water if they weren’t oriented with the opening face down so they would be sure to drain. We also had compressed air to hit it with before we’d put it in the dryer so we didn’t have to worry about the water leaving spots.
But the bottom line is, you can hose the entire thing off with soapy water, rinse with plain water (or if you’re concerned about waterspots, distilled water), as long as you let it dry thoroughly. Immersing it in soapy water would be fine as well, just make sure you shake it off, and/or blow it off with one of those canned air dusters. In any case, then leave it in a warm spot for a few days to make sure it’s completely dry. Or you can hurry it up a bit by putting it in the oven at a very low temp if your oven will go that low (mine won’t, it’s lowest temp is 325-- you don’t want to use more than about 140 degrees max, and most definitely DON’T use the microwave, that’d burn it out for sure).
Even old equipment that uses paper capacitors can probably be treated this way, as the paper caps are wax dipped. Though that might be the one thing to be a little more cautious about, as I suppose they could store a charge. In all cases, as long as you rinse it well and be sure to let it dry thorougly, the water isn’t going to hurt anything if there’s no power involved. Note, that if the device has a coin battery or other kind of built-in battery, that would be an issue and you’d want to remove it, but I don’t think Clouds has one-- the “memory” it uses to retain settings is a battery-free NOVRAM or similar I think-- and since it’s pretty easy to look “inside” it, you should be able to check to see if you see a small battery or not.
At Tektronix, we never had a failure due to the wash, and never had to repair old dusty, smoky, grimy, greasy, or mouse-infested (yes, that happened), or soda or coffee spilled-on test equipment. And everything was then returned to the customer nice and clean, tested, calibrated and fully operational up to spec.
If all that makes you nervous, then just take the knobs off, take the panel off, then scrub the crap out of them with whatever cleaner you’d like to use, and you’l be fine as long as the smoke hasn’t permeated the electronics so bad that you can smell it even when it’s enclosed in your rack…