Making dedicated tool

We needed a 80mm spanner to tighten a hard to reach nut on cilinderhead #1, but we only could find one that had a width of 75. So Wim did some grinding until it fitted. So after that I climbed on top of the engine with the "new" spanner and a small sledgehammer to tighten the nut a bit more. Why we did that? Well, exhaust gas escaped between cilinderhead and enginecasing. And it worked out well.... no leaking anymore.