There are a few possibilities for the turbocharger enthusiast. One source would be Mike Arnett--Silver State Motorsports. He offers a speed density based kit that includes the turbo, wastegate, bypass valve, header, intercooler, crossover tube, custom chip, 36 pound Motorsport injectors, high flow converters, large truck mufflers, and a custom chip for $5,995. I may have left something out, but it's truly a complete kit. If you have any of these components already, he'll give you credit for them and reduce the price.
The other source I found was at Cartech in San Antonio. I spoke with a gentlemen named Greg who seemed very eager to help and knowledgeable as well. He worked up a similar setup for a much cheaper price. I tried to follow up a couple of times with no response. He mentioned they had previously outfitted 3 Lightnings with turbochargers.
The most recent research has brought me a gent named Shane Hill who is a frequent poster on this list. Shane is opening a new speed shop soon and he mentioned plans to put together a turbo kit for the first gen Lightnings. I spoke with him not too long ago and he was able to successfully answer the plethora of questions I bombarded him with. I am very excited about what he can offer the group of us eager to turbocharge our trucks. He said something about plans to offer a single turbo kit or perhaps a customized twin turbo setup around mid summer. He's forecasting 2 levels of power to choose from--550 hp and 700 hp. He seemed to be open to suggestions and customer oriented as well. Hope this helps.