Hard to fit a Listeroid on the rear of a go-cart..........
That would kick ass, a 10hp diesel go cart, maybe with a torque converter drive-

I have an SL-3 I am going through now, hooked to a 7.5kw marine generator.  I know about the carbon issues with these engines, and it most likely will be used to charge a large bank of batteries so it won't be running at partial power very much.  I am also considering turbocharging and hooking it to a larger generator, but that is a ways off.
The idea I am running around with now is to set up a ~250gallon heating oil tank with insulation and a heater, fill it with WVO, and use that to fuel the generator.  I do plan on being many miles off grid, so this will be my primary source of power.
Anybody have long-term experience with this engine on WVO?

There is no advantage to using dual belts. Use one belt that is big enough to transmit the power. Keeping things simple is a great advantage. It is vital to establish correct tension. If you use a gates belt then you can consult for free with gates and they will tell you exactly what tension to apply. They are experts. They are free. They make very good belts.

I agree on that point-  When I have the money, it's Gates belts.  I have actually found "Mileage Maker" belts from CSK Auto/ Advance Auto to be halfway decent.  They are made by a spinoff of Dayton Rubber, IIRC.
Don't waste your time on Goodyear, especially the "Gator Grip" or whatever they call those stupid belts.  Noisy, and they crack fairly early in their life cycle.

As a point of observation:
The total load on a car serpentine belts, with a/c and power steering, is about 15-20hp and they are automatically tensioned.  They are fine WAY past 3k, I've had serp- equipped cars to over 6,000rpm.
Also, those big fancy 6" chippers that will take an oak branch and shred it to little tiny pieces in a few seconds-  Those use (typically) a 22-24hp Honda twin, and the flywheel weighs about 150-200lbs depending on the model.  The engine spins at 3600rpm, the cutter wheel at about 1500, and connecting the two is a dual 5/8" belt.  It's fairly reliable, and I've only had to change them out due to customer negligence. 
My compressor uses a small polyvee belt, works fine on a 3200rpm 2hp (actual) motor driving a 2cyl 1400rpm compressor.

A vane pump, supercharger, etc has very little effect on a diesel-  the 2stroke GMs used one simply for scavenging, and bypassed it at higher rpms. 
Turbos are much more efficient, especially on a diesel.  They are only there when they are required, and they are not constantly trying to shove air in needed or not, constantly dragging on the engine. 
Extra air by itself won't hurt the engine, but it won't help it either-  you need to add fuel to increase the power.  Possibly make a calibrated diaphragm to open the fuel rack a little more as the pressure increases.  I wouldn't a DIY turbo setup without an EGT probe for sure, though-  extra fuel means much, much higher exhaust temperatures, and the temp can rise significantly before excess smoke shows up. 

Does anybody use this particular alternator?  This one has been sitting for a while, anything to watch for with it?  Or is it just wire it up and go?
The bearings seem ok, it turns over very smoothly and dead silent.

I've had to blow out my wife's Dell a few times, I've even had to blow out my desktop's CPU heatsink and power supply several times.  It's a problem with anything that has air moving across it and changing direction rapidly-  the dust suspended in the air drops out and clings to the surface, building up and as a side effect insulating the heatsink until it no longer functions properly. 
BTW, if your computer gets slower the longer it is on, clean the CPU heatsink.  Guaranteed to pick up your speed with a cooler CPU.