CUJET:
I recommend a 10 foot container for your needs. This is based on my use of a similar unit, only 20 feet in that case. If you need to sound proof it, rock wool panels inside with a dead air space between them and the container walls will do wonders. I have no interest, financial or otherwise in this company, other than as a very satisfied customer.
http://affordablespacetrailers.com/
Also, If you don't want to go to Orlando, Armelini Trucking here in Palm City has some containers to sell. Again, no financial interest, etc.
I used a 20 footer that I purchased with a damaged floor to build my services and utilities space on the farm in Alabama where I hope to retire in a few years. Removed the remains of the wood, poured the floor with concrete and added the mounts for generator and engine bases, water heater and pumps, heat exchanger and solar controller with panels on the roof. 6 fork lift batteries in the closed end with venting and air management as needed. 15 feet away with a 3.9 liter cummins running at 30KW / 1800RPM all you hear is a light hum and guiet rumble.

My 6/1, Rene' will get a 5Kw next weekend. Providing the seller in Georgia still has one.

Used 1.75 gallons of red dyed #2 diesel in 8HRS. at 645RPM, full rack travel after 15 minutes start-up/warn-up. Still using the compressor for a lpad since I can regulate the load so easily. Oil used was about a pint, with some in the exhaust, just a hint of a blue tinge. Best results on compression was all the way in, calculated to be 18.5/1 with     .075 head clearance. I'll run the same again until Sunday, with a partial teardown on Monday. I did see some clag on the magnet after shut down, so I'll change oil in the afternoon when I shut down.
Every kid in the neighborhood was here at some time today, and most of them brought there children with them. 

I agree with 'tater. The "best way" (in quotes because the best way IMHO may not be the best way for anyone else) if you are only going to run a 6/1 is to run it as a battery charger for a HUGE battery pack. Then run a system of inverters to actually power the shop. This way the 'loid will only need to work at it's maximum effort, not try to keep up with a super large demand that it cannot handle. Stack a set of Outback inverters, and use the matching transformer between them. That way the batteries act as an accumulator and supply the load. THIS AIN'T CHEAP. Your alternative is a larger engine / bigger genny and more fuel. Don't forget also, a bigger engine running under lower load will be much less efficient than a smaller one. Run the 6/1 all the time you work, with an auto shut down when the batteries are fully charged.
Just my tup'ence. Wayne.

Tugger:
That is a Class Act!!!!! I especially like the fence and lifting beam set-up! Real sweet.
Just one question though?
Shouldn't the water pipes berunning at an upwards slant to the tank?
AND NO, I DO NOT WANT TO START A WAR ABOUT COOLING SYSTEMS!!!!
I'm not asking anything, I'm just asking.

Folks:
This is in response to an E-mail I got 2 days ago with a ctitique of some things I wrote earlier, and this gives me a chance to answer this as well as provide some thoughts as they pertain to this thread.
I've got a L/N 24 volt alternator spec'd for a  Kenworth wrecker. New, never installed, bought freight salvage. This unit weighs almost 25 pounds. The interesting thing to me is that it is intended to use an external regulator, thus has none internally.
This makes it ideal for "our" purposes. I'm setting up the 3 cylinder Deutz 2011 I got recently, with a 15KW ST head driven by a shaft from a stubshaft to flywheel adapter by Hayes Mfg. aided by a short telescoping shaft. This allows room on the genny shaft end for a pulley (sheave) of 6 to 8 inches diameter. At 1800 RPM for 60CPS, I want to drive the L/N at no more that 4000 RPM to extend the life of the bearings, and cut down on the losses from belts ETC.
The part that holds my  interest here is the chart published by Prestolite giving output VS rotor speed. Within the spec sheet for this unit we laso note that the Maximum, Never Exceed, Redline, Blue Limit, "Cap'n, She's Gonna Blow," Kaboom into small pieces speed is 8000. (OK, so I'm dramatic and a Star Trek Fan.)
The point of all this is, Whenever you can, take pains to read and understand the specs of the parts you are using. Automobile alternators are the greatest things invented, BUT they were intended for use in cars where most of the time they were at or near engine idle speed. You know, Police cars. They, along with Taxis drove the developement of these things.  Truck engines, on the other hand run more slowly, spend less time proportionately at idle and are heavier duty all around. They are also, with the better quatiry units such as those intended for emergency vehicle use, more frequently equiped with external regulators, externally mounted diode packs, (rectifiers) and are usually rated for a higher duty cycle and speeds nearer those WE USE.
Now, for most of us, weight isn't an issue. Well, for our engines anyway. (A full race aluminum Listeroid with a magnesium ST15 head? Never happen.) I'll be using the heavier, easier to work with, probably older and in my opinion, more adaptable technologies. This doesen't mean I'll be ignoring the latest tech when it comes around, but I'll look carefully at it and what it replaces before changing things. 
In closing this rant, I spent most of last week with my friend Michaels family, clelbrating his 80th birthday, and GENTLY pumping him for every scrap of info about balance I could. He is an 80 year old, opinionated broken eglish speaking Cuban, who knows more about engine machining than any 15 people I can name, and I learned a lot. Look for a lengthy post or series of posts in the next few days.
Best to All and "Please give my love to your Mother." (Quote: Kevin Kitchens, local radio celeb, deceased.) Wayne.

FWIW: I'm building my 6/1, Rene, to investigate this system, and will be negotiating with Mr. Crower for an R&D liscense in the future. Plans also call for a flywheel mounted homopolar generator and inverter on this engine.
Wayne.