Try here:
http://www.soec.org/index.html
If I'm not mistaken, they have access to records to verify serial numbers, trim/colors, and original options. Maybe even keep anecdotal history like SAAC somewhere.
I think these have good (but by no means guaranteed) collectibility potential for the future, since Saleen is (was) a manufacturer and not just a tuner shop. For a generation into 5.0's, these were a high water mark, much like the '93 Cobra.