Also try to find out what if any options Saleen installed originally on the car. Even if the car did not have a supercharger installed by Saleen 1994 seemed to be a weird year for the way S351s came optioned. Being the first year of a new body style and a brand new model for Saleen there were no real option packages like in 1995 with the T code or R code option packages so owners/dealers would pick and choose which specific option the car would get if they opted for any. Also body style sometimes comes into play like if its a coupe or convertible. If you have the car number and the last three of the VIN anyone who has the Saleen book can do a quick check to see what options came on the car and if it's a legit Saleen.. That or you can call Saleen directly and see if they will tell you. Otherwise you may have to buy a letter of authenticity which will tell you exactly how the car was built and if yours is a one of one or how many may have been built like yours.
http://shop.saleen.com/product_p/12-014-00001-01.htm