cleaning up underside of vehicle

I shot a vehicle, in motion, using a camera rig and need to photoshop the rig out, what is the best way to clean up the ground under the vehicle. Also,Is there anyway to change the clone stamp pattern to a square rather than a circle?

if you could post the picture that would be the best, that way I could give you proper advice depending on what you got to work with.

But your probobly going to want to use the clone stamp like you mentioned, and yes you can change the brushes. But you'll prob want to copy and paste different sections and blend them on top of your rig. Again its really hard to give the proper advice without the pic, so if you could post it up I'd be more then happy to point you in the right direction....

sent it to your regular e-mail
,thanks