most of the pieces you will need are in car and caravan set 4435.
get these pieces and put them together. these will be part1
do the same to this one. we will call this part 2.
it's hard to see so the pieces are: any color 4 by 4 piece, two gray 2 by 1 striped piece. we will call this part 3.
put them together this is part 4.
this is the body.
attatch these to the body.
attach these to the body.
attach part 1 to the body.
attach part 2 to the body.
attach part 4 to the body.
finally, attach wheels to the body.