You can get Paul Gilbert's sound. However, you can never get Paul Gilbert's tone. The difference is, tone usually comes from the fingers. Buying the same set-up as Paul Gilbert won't get you near to Paul Gilbert's tone. It's not like a tome of paul gilbert X1. Anyway just for a guideline, he has high treble, middle mids and low bass. He cranks the distortion on tube amplifiers and uses a Majikbox Fuzz Universe to add a little more gain.
His set-up:
GUITAR: New Ibanez PGM301, vintage Ibanez guitars
PICKUPS: DiMarzio Tone Zone, DiMarzio PAF Classic
PEDALS: Ibanez Tube Screamer, Fulltone OCD, Xotic Effects AC Booster, Fulltone Soul Bender.
Then again, it would be crazy to believe that he has only used the abovementioned pedals. He probably has a room full of pedals which he has not shown/revealed to the nosey guitar-geeks-like-you-and-me/tone-whores/guitarworld/guitar-news-people.