That is quite an impressive build you did! I have wanted to do something similar for quite a while. Sadly, everytime i start building my offroad vehicle, i always end up building some kind of death machiene to murder sheep with for some reason. Oooh well. i guess that is the effect this game has on me :)

I usually start with the suspension or some other mechanism. Then I test it until its smooth and then build whatever wants to be built on top of it. Somehow, mech-oriented design keeps me focused. :D