You're right, it don't cost $25,000 to put one together, Ice already told you it only cost $5,200, the other 90% is mark up and profit.
By the way, my Seville SLS, a class or 2 above the DeVille, has lots of plastic under the hood also. Not a lot different than what my C5 has. It's hard to pick the one I want to drive, both are so near the same comfort level on the road, now getting in and out is another story, along with the fun factor.
Just for kicks I went down to the local Ford dealer this afternoon and sat in a red Thunderbird that has a light brown leather and plastic interior. Smells good, feels alright, but just don't make the grade for being better than the car I got out of. I still like the car as a whole, I think they did a fine job. It will sell and will become very popular if present buying trends holds a little longer.
One thing is for sure, we won't lose many Corvette Club members to the Thunderbird, if any.