Just get an angle grinder (electric or air) and start hacking away at the backside of the front clip where the grille is housed. I guess you could remove the front grille. Otherwise tape up the outside of your front end, after you remove it, so you don't scratch it, and start grinding away. I thought this was too tedious so I went a different route
I made a router template out of aluminum that fit inside each of the honeycombs, and used a step drill, then a dremel to finish off my grill. I recently hit a large chunk of semi truck tire that wiped out my front end, including my grille, so the dealer used my template to get the new front grille looking like the old one did. They did a real good job. I'll take pictures and post them later.