Here is how the SKS P55s fit on my 50cm LHT:
At the seat stay. Just fits - any bigger and you would have to bend or trim.
Here's a shot from the left side at the chain stay. Again, it just fits with no need to bend or trim. Note: presta nuts make perfect spacers to help get a clean fender line.
From Drive side
Overall shot. Clean lines (at least in my opinion.)