I've got an inverter that I want to fit ready for the summer. I was thinking on doing it like DandyW - above the metal bar near the glove box like this:

A couple of questions though:
1) What's the best way to route the cables through to the engine bay? There appears to be a grommet behind the coolant tank, but on a quick look I couldn't see where it comes through on the inside. Can you use this?
2) Any advice on removing the glove box without breaking anything? I am always nervous of applying brute-force to trim parts (particularly as the plastic is starting to get a bit old and brittle)