I've turned up a couple of these, but it's been several years...
Having said that, I believe on the passengers side of the injection pump there is a small plate held on with two bolts or screws that allows access to the "fuel screw"... Bar the engine over until you can see a small allen head in there, turn it clockwise as far as you want, depending on how much smoke you want.

I think it can only be turned in something like 2 1/2 turns. If he still has stock exhaust and intake, I would only turn it maybe 1/2 to 1 turn and see what it does.
And yes, you can also advance the timing. Just loosen the bolts holding the pump on, and rotate it as far as you can i believe to the drivers side, then tighten the bolts. You can't turn it too far as the slots and also the injection lines being attached will limit the travel.
(Someone double check me on the to the drivers side part, I always get confused because you turned the Chevy 6. 2's (with timing chain instead of gears) the opposite direction. )
And yes you used to be able to get turbo kits. (Should still be able to?) From Banks or ATS but I don't know if your boss wants or needs to spend that kind of money for what he needs to do with it.
Good luck.