The site was probably Frans’ spacequest.net:
“An early release of Space Quest 3 is somewhat different. One obvious difference is that the Aluminum Mallard’s cockpit computer had the option “Lite Speed” instead of “Light Speed” as seen in later versions.”
It doesn’t list what version of the game it is, but perhaps in the Janitorial Times forums of spacequest.net you might find the original discussion.
I don’t think anyone has the THG release of SQ4. I’ve never seen it. I had a text file from THG at one point with all the info about the release, but I can’t find it right now.