There is an awesome convertible variant of Natanael Kuipers Concept Car (more informations about this wonderful supercar MOC can be found here: http://www.eurobrick...oncept Car&st=0): (gif animation stolen from TB - http://www.technicbr...ept-car-by.html - a very good description of some variants of the Concept car) It is a very well designed roof with a reliable and robust gear-driven closing/opening mechanism. It adds great value to the concept car. And the whole roof fits pefectly to the outstanding modular design because the whole roof is one modul which can be mounted with just a few simple steps and with effortless ease... Well, currently you can buy perfect lego-like BI for the concept car but unfortunately only for the basic car and not for the gullwing and convertible variants. I asked Natanael if he has some better detailed pictures of the roof mechanism as available in his brickshelf folder. He has generously send some to me which allowed some better views... thanks a lot, Natanael! On this basis i have now managed to reverse engineer the roof-components and have made detailed step-by-step photo building instructions. I have uploaded them to brickshelf: - step by step instructions for all needed components: http://www.brickshel...ry.cgi?f=540360 - all needed steps to mount the roof-components to the car: http://www.brickshel...ry.cgi?f=540361 (Each file name contains the step number) Here is an example of the level of details of this BI: I'm quite sure everyone can easily follow these instruction steps ;-) An excel part list can be found here: http://www.brickshel...ry.cgi?f=540359