hey,
i done the tut on the z4 on 3dtotal its in this section somewhere
it is a good tut but a little limited an u end up making ur own way 70% of the time but worth a try

personally i would restart the mcclaren as this will get u ready for later on in life wen u cant chose adiff car wen u r boss asks u for a ford escort an u give him a beetle

good luck though