There's a bit more than 86 Lexan Sliding Windows F40s, and they are spread throughout the production run most of which are non-cat non-adjust. Also the type USA cars are a separate series of cars created after all variants of Eu cars were already in production. If you want to group F40s into series, there are at least 4 series of standard road cars.
The initial batch of 50 odd sliding window cars were produced before the adjustable suspension was ready, sliding windows became an option only a few took up after that. Cats were mandated in Europe from early 1992 so all examples after that date will have such fitted. All US spec cars had wind up windows, cats and were non adjust.
I just saw a very good F40 with sliding windows, cats and adjustable suspension a year ago. Was a late 92. Quite interesting!
The highest serial number I've got listed with Lexan windows is 94030, new in September 1992. Last noted (by me) at DK in 2010 with 16,500km. Even higher is 94612, but unconfirmed.
I have 96 production cars with Lexan windows, but so many more unknowns !! Every month a new discovery. Over 110 wouldn't surprise me .
Thanks for clarifying that. Yes, Marcel has pointed one or 2 cases that have come to light. 91 it is !!