I recently bought the Ferrari Garage LEGO set, for the 250GTO. It is pretty good, but it was the 312t4 which took most of my attention. It was good looking, but ill-proportioned.
Original 312t4 is an odd-looking ground effect car. With its double-decker front, very low sides and rectangular body, it has this "ugly but effective" vibe, which was - to me - somewhat lost in LEGO version.
I tried to fix it. It ended up being a bit more than add a plate here and there and fix some proportions. Eventually I built the little car from scratch and gave up trying to fit entire minifig inside, it just made the upper section too wide. It still is too wide, to be honest, but seems to be a reasonable compromise.
All the stickers are taken from the original set, just recut and placed more appropriately.