1947 GMC COE 20,000 orig miles!

[01chevduramax]

Hey guys,
I did some electrical work for a guy. Went to his shop 3 times or so. Got a decent look at his monster flatbed COE. It's a 1947 GMC COE. Pretty sure it's a 5 ton. I don't know much about them. It was his grandfathers truck bought new. He showed me the original title from '47. Also showed me a photo book of the restoration. Rebuilt engine, axles, brakes, etc. the flatbed is custom. It's beautiful. Guys 70+ year old machinist. he is interested in selling it. I told him I'd post about it here. Try to find out what it might be worth. I'll attach the only picture I have of it. not sure why it's sideways.
Please give any info you have. Thank you!