Wow!
That is going to be one heck of a beast.
Hope he has a low-loader in his driveway 
Those castings look nice, but hope that the 'white' where the've been foetrled is just reflection.
You are lucky to find a foundry prepared to do 'small' one offs.
Are you using SAR drawings?
Do please post photos as this project progresses.
If I was younger, I'd be twisting someone's arm for a set of castings!
Wish you both well with this build.
Geoff – Planning for tomorrow's stint in the workshop.