Will this fit in my dash if I trim the opening a bit? It's only a half inch bigger than the opening:

http://www.sonicelectronix.com/item_...KW-HDR720.html

I've seen a thread on here where someone modded in a unit with a 7" LCD panel, but I dunno if that stereo will fit. So, will it?

Again, I know I have to trim the dash a bit, but what do I have to trim and mod to make it fit and bolt in?

 

I know on the Fieros you have to do some trimming on the plastic, but there is also something behind the radio that hold the factory one that needs to go. I'm not sure how identical the fiero and third gens radio set ups are, but I assume their intalation are close to identical.
IMO I would go with a single din, that radio is a cheap replacement for a factory double din car. It definitely is not worth the work considering it will be no better than any single din of equal value. But if you were going with a touch screen double din it would be a much different story lol

 

that's a double din setup, so same mods as any other double din radio - custom brackets to hold it in place to the console, trim bezel for height, and fill in/blend for appearance