Best of luck Tasdrouille. Can that u-bolt not rotate a little so the bolts are horizontal, or even on top? I know, it would make then harder to get a spanner or socket on but might be worth a try. You could even try a large jubilee clip. (is that what you guys call them?!) That would be clean and the bolt on that would be most accessible when on the side of the exhaust.
ollie
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