I put my new carpet in last weekend and plan to put on the finishing touches this weekend. My question is exactly where do you trim the carpet at the step plate. Should it go all the way out on the flat where the step plates are screwed down?

I usually make sure it goes just past the point where the screws go through. As long as it lies correctly under the plate, I try to have it well anchored. If you are going for a 'factory correct' install, you may want to consult the assembly guide for your year. MOST Importantly - Don't trim it too SHORT!
-Bill

Did what all doc said,and also had my seat sitting in vehicle so would make sure wouldn't pull away from edging when installing them.Same mine just little past the holes.

got it! thanks guys!