This is the great set 8066 modified to become a mini version of the 8081 Extreme Cruiser.
About this creation
There were quite some heavy modifications done to this little set. Listed below:
1. Blue Seats
2. Light grey shock absorber. This is done to make it not stand out as much. Also, I made 8066 from my own parts, and I don't have a yellow shock. A rubber band was added to make the suspension stiffer.
3. Doors. They can't open, but at least they're there.
4. The roof: The most noticeable mod, I made the angles as accurate as possible to 8081.
5. Half module-wide red stripes. I had to widen the front panels a bit.
Quoting Lego Technic 17
Where is the building instruction?
In the land of non-existence! If you're really interested in making it, start by building the set 8066. Then it shouldn't be too hard to build the rest by adding/changing everything listed in the end of the post.