SB 13-08-08 Failure

I was getting ready to install the freshly engraved data plate. I thought it to be a good idea to keep the stainless steel plate separated from the aluminum surface it is supposed to get riveted too. The way to do this is by applying primer.
So I located and masked off the area where the plate is supposed to go.

Then I scuffed the area with an SB pad and cleaned it with Acetone and applied the primer to the aluminum as well as to the back of the plate.

It was too late in the evening to hope for a quick dry so I could continue with the drilling and deburring and riveting. I decided to just let it be alone and move on to do SB 130808, which I consider to be my personal Service Bulletin. That's due to the fact that I made Van's aware of the problem of the mismatch between a M5 nut on a AN3 bolt. I had already found a solution in putting a metal lock nut on the bolt but it was a different than the one Van's now wanted to be installed.
This is why I decided to mess with an otherwise perfectly working system (hint, hint).

Here you see the new nut in my fingers and the installed nut that I had chosen. I removed the metal lock nut and put on the new one. Finding the torque value was a hassle and I had to dive into the Rotax documentation to find 35 in-lbs for this bolt (if it was the original M5 bolt). I set my torque wrench to what I thought to be 35 in-lbs and started screwing. I was surprised that it did not unlock and kept on - which was the ultimate mistake. After a moment I heard a sharp crack and I new something had given in.
It turned out I had accidentally set the wrench to 55 in-lbs and the AN3 bolt, weakened by the hole drilled though its shank, cracked.

Van's web store does not list these bolts, so I sent an email and will follow up with them in the morning. Sure it's a long weekend ahead and so it will probably take until late next week before the replacement is here. I ordered two - just in case.