If your motivated there is no reason you can't do it yourself. There are a few pro's out there that have body jigs for this kind of stuff and could get the job done very quickly.

The nice part is you have a coup so not nearly as much bracing is needed. Your doing the right thing by researching this. I would jump on the camaro forums too and see how they are bracing things up for a job like this.

I would think that you would want to do the floor and the rockers at the same time with a bunch of vise grips. These are not NOS piecse so who knows what you might run into.

I would plan on having a bunch of square tubing on hand and make X braces on the inside of the rear 1/4s and the Cowl and a X brace between the driver and passenger side. Once things are tached in place I would put the door back on and check the bottom of the door and the 1/4 gap.

I have did a buch of metal work on my car but never rockers.