lol here ill post my how to lower a car pic, well photobucket is down atm...
as far as the other wheels i used were from a different image, they were slightly darker but i darkened them a little more.. just select them go to image>adjust>brightness/contrast, then just lower its brightness a little bit to make it look a little better.... you can also use the burn tool on parts of the rim where it would normally be darker
how to lower a car........
take your lasso tool (L), start at the bottom of the car working across the bottom of the car, then go up into the wheel well, making really close together clicks to keep it more circular then go straight from the bottom edge of the car off the image, then click to the top of the image still off the canvas, then over to the other side, then back down the image still off the canvas... then simply go back the the corner you started on and make the ends meet...
then hold down the CNTRL key and press the down arrow till you meet the proper height you want.....
dont forget to crop the top of the photo off afterwards, as nudging the selected areas takes the entire picture and pushes it down.
did that help any, if not i'll post the pic i made