IIRC the last twelve built were special "one offs" with Lamborghini style doors, rear spoiler etc and 11 went to Japan and one was kept by the factory. I can't remeber where I read this - maybe Auto Italia? but no doubt a good GOOOgke will reveal all.....
The barchetta-Lexikon (www.barchetta-lexikon.de) gives a production figure of 57,521 on its front page. However, they also have a page (http://www.barchetta-lexikon.de/?action=farben) where owners can submit the VIN and the colour of their car. That list currently goes up to 57849. That seems to tie in with the research by Zem in the thread above (see post no. 21). He found that the last chassis listed (in ePER) is 00057890 - vehicle number 00057661 - Production date June 2005.
How does this (small-ish) discrepancy in the figures come about? Perhaps Fiat built a number of development prototypes which were given chassis numbers but weren't sold (in which case the figure of 57,521 quoted by the the b-Lexikon as "production figure" might instead be a sales figure). Or is it due to sloppy record keeping?
I have to say I don't understand the difference between chassis numbers and vehicle numbers. What is the distinction between the two, and why are there separate numbers for chassis and vehicle? I would have thought that only one number would be needed (VIN/chassis number/vehicle number/whatever) to identify a vehicle by.