Only the Company Honorman graduates as Lance Corporal or E-3. My husband was the CHM for his graduating class.
He sacrificed a lot of his time and sleep to help everyone in his platoon. He worked incredibly hard, got excellent PT scores, studied like crazy, got top swim and rifle qual's. You have to be appointed the guide of your platoon before they even consider you to be an honor graduate or Company Honor man. You have to be the best of the best.
It is an extremely competitive thing to get. Before you go in, study up as much as you can do give yourself a better chance. It sounds like you'll go in as a PFC if you recruited someone (unless that policy has changed) and that's great.
Here is a link for the naysayers who say graduating at E-3 in the Marines is impossible. Just scroll down. (No, that's not my husband, just the most recent class.)
http://www.mcrdsd.usmc.mil/