I have Standard / Tourer on my Interstate I didn't cut anything.
You had to take the pods off to put those on, like I did also. But, I have POD lights and the brackets clamped to the engine guards under the PODs interfere with them and they would not go on. I had to trim about an inch off the front ends of both pieces. Really can't see that far up behind the POD toward that bracket.
But.....maybe that is why I bought those years ago, knowing they would fit the IS as well as the others.