Looks too good to be true unfortunately, I found the below with a bit of digging.

It's about halfway down the page, I couldn't upload the pics as they are too big.

https://forums.nasioc.com/forums/showthread.php?t=2849900&page=2

 

 

 

And more detail of the cutting on page three. 

Cheers 

Bennie

He notched the frame rails for the dohc engine on page 3.