well here's what i can say on that.......stock to stock, my 83 or 89 never saw the back end of one of those. nor did my boss's or friends corvettes or camaros. the numbers above that i posted also don't line up with what you're saying. i'm thinking you were talking modified to stock to be honest, as also having driven them, i was able to understand why. working on any of them, from the basic to the higher end, pretty much made me hate em, although the 2.2 and 2.5 timing belts were pretty easy.
Inasmuch as only 500 of the GLHS were built, I'd very much doubt that you ever saw one on the street. Most were sold in California and in the New York tri-state area. There were plenty of the GLH Turbos, but those were far less capable than the GLHS. I saw you posted 0-60 of 8.0 seconds for the GLH Turbo. However, that's way too slow. Typically, 7.3 to 7.6 seconds was where that little car ran. I'm thinking that you are confusing the GLH Turbo with the GLHS. The GLHS came in black only and was a much different beast than the common GLH Turbo.
My GLHS was very quick bone stock, and engineered to out-handle just about anything on the street. I was able to obtain a Turbo III set-up from a wrecked R/T (brand new car, had only 2,200 miles on it when run over by an oil delivery truck) and we transplanted it into the GLHS over the winter of 1990/91. A Stock Spirit R/T could run 0-60 mph in 5.8 seconds, according to an October 1990 Car and Driver road test. Now, put that engine and transaxle into a car weighing 900 lbs less and you can imagine that it was pretty dang quick. That transplant was not simple... Like any other engine swap, things you believed would fit, didn't. Wiring changes and motor mount adapters had to be fabricated. Many other details had to be addressed. In all, it took almost 5 months of evenings and weekends to get the GLHS on the road. In succeeding years, I added an aftermarket Shelby logic module, adjustable boost regulator, adjustable wastegate bleed and much more later. The stock Turbo III engine made 224/225 hp. It ran great on premium fuel, but required Sunoco 260 if I dialed up more boost. Custom blend race fuel if I really cranked it up. I replaced the factory Centurion wheels with American Racing wheels and bigger rubber. Head gaskets frequently failed with increased boost. Turbos would blow seals and become external oil pumps. When that happened, it looked like a mosquito control vehicle.
If you look, you may find one today. But most have been modified and many wrecked. Still, it's a great project car that will offer great performance for very little investment.