69 Corvettes had a nice steering wheel so I'm not sure if Motion changed the steering wheel on the 69 MP Corvettes. In you look at the pictures they look to have the stock wheel.
If the customer wanted to change the wheel they may have used the Grant Wheels like used on the Camaro Chevelle Nova
I have an old Grant wood wheel that is 13.5 diameter
it looks similar to the wheel that Grant still sells as the "Classic Wood Wheel"
not sure if the new one is exactly the same as the old one
http://www.grantproducts.com/products/view/5/