Welcome Chris, nice car, love those satellites in silver.
I think Pete'Bananarama! the nail on the head, it depends if you intend to keep her long term or not. If you've got her for the long haul and want to clone her as a GTX then do it. If not keep her small block and get some use out of her.
With regard to your questions on value, unless your planning on doing something very very special then from what i've seen stock and numbers matching seems to beat a clone any day.
you could always ask Jon about how to make a small block go fast....he seems to be a bit of a wizard when it comes to that.....
