Interesting one Frank. All of the others including mine had the crack on the other side of the frame and had the latter mountings for the locking clasp.
I had a fantastic response from Iain Rhodes at Ducati UK and my SL at the time was 7 years old and he did not ask for any service history. I just took it along to JHP, where John took a picture and three weeks latter I had a new frame deliverd to the door. I think as a result of one of your replys to my original post. Give a go and who knows.
Cheers Allan R