What tool do you guys use to cut body sections with?

[Russell Ashley]

I've noticed that some of you can cut a long perfectly straight line when doing panel replacement. What do you use? I use a die grinder that is rated at 20K RPM with a thin three inch brasive cut-off wheel that is also 20K RPM rated. It seems that I can never get a long cut as straight as some of you. The wheel grabs and the cut winds up a little crooked. Is there something better to use than the cutoff wheel? I've got major surgery to do on my drivers door soon and it looks like I will need a straight cut across the door to fit up a new lower door skin. I don't mind buying a new tool if there's something better out there.