The Hedmen web site sayes that they're good for the 82 - 00 model years. It lists small blocks between 283 - 400
Must use Trans-Dapt Performance motor mount kit #9906.
You might have to run a floor shifter with them
Standard transmissions won't work with these headers.
The S10's are listed about 1/2 way down this page
http://www.hedman.com/pages/hedmanmain.html
Hedman also has a good reputation for their customer service.
Here's their contact info
http://www.hedman.com/pages/hedmanmain.html
I hope that answers all your questions Doug, and have fun with that.