Great job on improving the Olds diecast. If you didn't mention it, I never would have thought that it was a diecast. It's unfortunate that AMT didn't go ahead with the Olds kit. I am not a fan of diecasts but I had to go diecast when I wanted to build a replica of my grandfather's 1950 GMC stake truck as I couldn't find any resin conversion kits for the AMT 1950 Chevy pickup kit. I found a diecast on ebay and unforturnately it looks more like a toy that a scale model. I plan on improving it and hopefully it will look as nice as your Olds diecast.
carrucha