The production portion of the VIN number in the dash is 612700. However, the body plate production number is 270007. Does this mean that parts were taken from two different cars? Or is it customary that 69 Camaros have different production numbers?

The numbers here don't have to match. There are a couple of hidden vins that should match your vin.

http://www.camaros.org/numbers.shtml gives you the info you want.

And the Model ID pages, e.g. http://www.camaros.org/diffs69.shtml, should also help.

Here's the scoop on the cowl tag body number:

http://www.camaros.org/bodynumbering.shtml