It’s high pressure die cast. There were s lot of mag parts on the 2005 (like the front core support). I can’t remember if the dash was mag, but that looks like it.
Discussion
It's an interesting piece of work. I do think it's magnesium. The more I was messing with it the less it seemed to behave like aluminum. I cut a small piece off to burn & then forgot to do it before I locked up, so I'll report back tomorrow. If it is then I'm really glad I didn't decide to take a grinder to it 😬