To answer a bunch of questions:
1) Nope, haven't done load testing yet. I need to build a decent load bank, or get enough of the same type of space heater than I can reliably add measured loads. I think it'll be OK on the radiator, though - heck, the "engineered solution" that came with it was just boiling off water. The wind from the flywheel is actually a pretty good breeze upwards through the radiator on the inboard side, and I'll bet that if I need to I could add a duct and fan bolted right to the outside of the flywheel plate pointed upwards through the radiator.
2) Yes, gloves and eye protection are pretty much constant for me. If you always have eye protection in place, you don't have to wonder about it or worry about where you left 'em. I depend on my hands for my day job spent pushing around a mouse and banging on a keyboard, so losing, crushing, or cutting fingers is also not on the agenda. I only take the gloves off when I'm doing things on the mill or lathe or other locations where getting a glove caught in spinning stuff would be Bad (and even then I wear rubber surgical gloves, just to keep the friendly hydrocarbons and heavy metal residues off my skin.)  I get a raft of @#% about my gloves and goggles, but that's usually from people with permanent injuries who are looking for company in misery.
3) I've got some ideas for a coupling guard, but it's admittedly not high on the list right now.  Maybe a plastic bucket with parts of the bottom cut out, and maybe with a "notch" on the bottom to allow removal, bolted or somehow fastened right to the face of the generator.
4) For details on the "real" Lister generator in the background, look at
http://www.loligo.com/projects/lister/ and click on the "pictures" link. I made the base out of 1" web thickness 10.5" I-beam, and the "shed" you see are powder-coated, galvanized panels that fasten on all sides around (and on top/bottom) of the stainless sub-frame to keep various arms/legs/livestock out of the dangerous spinning/hot/electrical parts of the assembly.
5) I'd be interested in how other people fare with better mufflers, like the underground rigs. I'm not sure if I can really do much more about the general noise of the mechanics and of the conducted noise of the cylinder, but having someone do a dB test with a completely silenced exhaust would be interesting. I'm still thinking about what else I can do on the intake side to quiet that down some more... Again, the phrase "5-gallon bucket" seems to call out to me, but I don't quite know exactly how it's going to come together.
6) I built this as a "semi-permanent" installation, even though it's still very much mobile until I get it into a shed of some sort. I use a hydraulic floor jack to lift one end in the air, put blocks under that end, then go around to the other side and jack that end up. Then I slide a heavy-duty caster truck underneath the whole assembly and lower one end, and then raise/remove blocks/lower the other end. It's _barely_ moveable on the caster truck - I figure it's about 750 pounds, maybe more, and the casters aren't so great...
7) What you can't see in the video are the small 2" wide x 6" long x 3/4" thick rubber vibration control pads installed under each corner. (McMaster Carr item #8981K158) - this absorbs a lot of the vibration between the mount and the ground, but I can still feel it 10 feet away on the concrete pad, though there is very little (no) harmonic vibration that I can see in the radiator tower. The muffler jitters about 1/4" at the most distant part, so I might brace that to the radiator frame somehow to reduce vibration hardening issues.
There's a 195F thermostat in the housing that is bolted to the top of the engine (George B's manufacture) which seems to do the right thing.
JT
