All fine graduates of the Peter Clemenza School of Mafia Hits. Notice that no cannoli was left at the scene?

Echoing the other commenters -- the only way to make an untraceable gun traceable is to have it in your possession.

And I'm glad Malandrino also noticed something that had bugged me too about using foreign hitters. After 9/11, there was a brief time where most non-Visa nations (Italy was one) weren't required to give prints, but that was changed around 2004. The Rusty hit was around 2006, if I recall correctly.