Let me tell you about my Zamboni project. It was originally modeled after the bright yellow Zamboni in service at the San Jose (California) Arena, home of the San Jose Sharks (NHL ice Hockey team) in 1995. It was one of a pair (one black, one yellow) with the Miller Genuine Draft (beer) paint jobs. What makes these two Zambonis more notable is that they both sported black shark fins.
I decided to build the yellow zamboni in 1995, while the Sharks were having their outstanding year. We had high hopes of getting into the playoffs, but I didn't have enough yellow parts. This need helped drive my future LEGO purchases for a while, looking for models with plenty of useful yellow parts.
I tried to make one that was the 'normal' 4-studs-wide, but it lacked the details that I wanted to see. As I looked more at the zamboni, while attending games and watching on TV, I realized that my scale needed to change. (I have actually driven a zamboni once. Yes, on an Ice Rink! It was an indescribable experience for me. :-) After all, the zambonis are taller, and longer and wider than most small autos. I started with 6-studs width, and this started to look much better.
The model began to take shape. Using larger wheels allowed me to change the scale, to add more detail, without appearing too large. This let me use a medium-sized wing element as the fin.
I call this the "bad luck charm", because, by the time I had finished the model, the Sharks had made it into the first round of the playoffs. And, on the night I presented it to our group of hockey-loving friends, the Sharks never won another game in the playoffs. :-(