He invested $100K into that?!?
I don't see it.
From personal experience, a really nice paint job, starting with taking the car to bare metal, can easily be 15-20% of that number - or higher - depending on how much body work.
Then you have the LS engine, T56 6 speed, suspension, wheels, LABOR, etc, etc, it can add up quickly. If the car was turned over to a restoration shop (turnkey restoration) to do everything, parts were probably only about 40% of the cost of the project -60% of it was shop labor. It can add up very quickly.