[boxhead]

I reckon the price difference from Glass to Alloy body is going to be $25-$30k. ($20-$15k by the time paint to glass is added)
The cost saving of not buying a glass body would be similar to the cost of having a chassis supplier make a frame to mount the body I reckon (purely a guess).

For the finish you are after (brushed and polished) if you are willing, this can all be done by you at home, cost is a lot of blood and sweat.
But to send a glass body out to be painted, you are going to be in for $10 - $15k (doing it yourself will still see a material cost of approx $2.5k)

A concrete painted car (sorry Andrew) will never be as nice as a real aluminium finished car (IMHO).

Is it worth it?
Only you can decide, but your desire is very similar to mine, and my answer is "Fark Yeah"