This is (or was) my largest MOC ever. It has now been sacrificed in the ancient tradition of supplying parts for the next model. It was about 24" long and I think 6" or 7" wide. The only real problem with it was that the front wheels tended to tip in under the weight, because I didn't have stong enough steering parts. Other than that and the steering wheel turning 1/4 turn before the wheels moved, it worked well : ) Sorry I only have these 2 pics.
Here you can see the hood raised and the lame V-6 engine. This happened becuse I only had 6 pistons and hadn't heard of bricklink. Those gears on the drive's side are so that both the pulley on the top and the steering wheel inside te truck can turn the front wheels.