How to fit a sprint booster.

Okay so I got my sprint booster today and I just wanted to know how to cut the metal in order for it to fit in place. I don't have an idea of what tool I could use without causing damage. Thankyou.
 
I think it is the best money I have ever spent. It is well worth it and when it's on race mode it's exactly how you would expect the car to come straight from the factory. I love it!