0484 LM in latest Cavallino

I was reading the article on the 121 LM in the AUG/SEP 08 Cavallino, (barchetta.cc page on 0484 LM here) and it made me wonder why Ferrari did so many changes to this car?? It had the chassis lengthened 150mm after it had already raced. Why would they do that to this car? Why not just sell the short WB car and make another one with the revised chassis? They also rebodied it before they privately sold it. What for? The impression I have is that it's never been too tough to sell a Ferrari, especially a competition model, so why not sell it as is? I'm thinking that all the time, effort, and money that went into modifying this car could have been better spent on a new one.

Maybe they weren't making as many of these cars as I assumed they were, so each chassis was precious?