It's my understanding that your X1 (#23) and mine (#24) were built on the "front edge" of the so-called "rescue/problem" cars. One person who might be able to give a more definitive answer (because he was actually there at Gennadi Design when our cars were produced) is Bernard Guerin, who resides here in St. Petersburg, Florida. His phone number is (727) 687-0981.
FYI, even though a production run of 500 GTX1's was approved by Ford Motor Company (thus the "23/500" on your X1 badge), the total number of GTX1's that were actually produced and sold was 28, or possibly 30, depending upon what counts as a "production" vehicle. I feel confident that GTX1 #23 and #24 are both original production vehicles. But speak with Bernard Guering. He should have first-hand knowledge to answer your question.
Best regards, and best of luck on the sale of your X1.
Steve Woodxrough
St. Petersburg
GTX! (#24) Black/Gold Stripes