This is what got me making cables in the first place!
Back in July of 1999, I started corresponding with a couple of guys who were working on hacking the PCM found in the 1994/1995 F-body and B-body cars. They had just gotten the communications routines working, and had a editor that was "roughed in" but needed some testing. So, I bought a spare PCM from my local junkyard and volunteered to be a "guinea pig" for the software. I helped provide feedback on operational characteristics of the software, and they kept sending me updates. :) Dave and Ken have been great to work with.
The software is called LT1_Edit, and (when used with my cable) it ONLY works on the 1994/1995 LT1 PCMs (that includes Z28's, Formulas, Trans Am's, Caprices, ImpalaSS's, Roadmasters, and Corvettes). It does not work on any other platform.
They also have an OBDII LT1/LT4 version available. I have the
OBDII cable and the editing software, and it works very well! I used to build the cables for
the OBDII software for Carputing, but I no longer do so (I built them from 2000 to late 2006 or so). It got to the point where I was just unable to dedicate the time to building all of the cables (goes back to "started the cable business when I had 1 small kid, now I have 3 rapidly growing kids").
You can check out LT1_Edit from Carputing at the Carputing web site
An alternative to LT1_Edit is another package from Tunercat at Tunercat.com. I also use Tunercat, and it has features that I like as well. I ride the fence on "which one is better" these days - there are features from both that I like and use. Tunercat supports more than just the 94/95 LT1 PCM - if you have an EPROM programmer, you can use the same software to tune a lot of other platforms - I've used it to tune 92-93 LT1 cars, 86-89 MAF TPI cars, 90-92 TPI cars, 1227747 Throttle Body Injected vehicles, my old Fiero, and others... It's a very versatile package, and certainly worth a look! I don't sell it either, but I do use it.