I'm sorry, but you can't have it both ways, on one hand he was more then happy to post photos of the repair, and I think it's a real credit to him a) for taking it on and b) doing such a good job.
You can't then try and retrace your steps to remove it "just in case"
It would be a far better approach to say " hey this is the car that came back from this incident, and look what a good repair it's had done to it"
The world of 260's is so small it would only be a matter of time before the new owner finds out.........and if you were in that position, how would you feel, especially discovering that everyone else already knew.
No 146 has a shady past, and I'm still trying to uncover it....but it won't shock me if I ever discover the truth as I bought it knowing this.