Diesel Do doesn't get on here too often these days.
Arch trimming won't be needed, as the arches aren't the closest thing. The spring cup is the point where large diameter tyres catch first.
The size your asking about has a diameter of almost 29.5", which could well catch on the spring cup with some brands of tyre. This could be overcome with thin shim spacers, between the wheel and hub. You'll need to inform your insurance though, as the tyres are larger than a standard fitment, and some insurers don't like spacers.