check out my car.... this is what i did (ive done it twice)
1. First i taped around the the grill, all the way up to the top slat of the grille, with duct tape (this way if you mess up while your cutting, you wont screw up the paint) Make sure that when u outline the grill with tape, to get the tape in the valley between the grill and the bumper, becuase when you cut the plastic tends to melt and plus the blade comes close to the bumper. Also tape where the emblem holder meets the top slat of the grille! More tape the better (believe me)
2. Then you need to get a dremel. Any dremel will work, but i recommend the ones you plug in with variable speeds. As for the blade, use a carbon blade because it tends to not melt the plastic as fast as a metal one would.
3. Now that you have all your stuff ready, you taped the grill off and you have the dremel ready, you can start the dremeling. Start at a medium speed under the toyota emblem.
4. Take your time and dont go TOO fast, it just makes things so much harder. Once you get to the bend that starts to go up on the bumper, cut into the grill as close as you can and raise the speed of the dremel, the plastic is thincker and the blade cant bend so you'll have to trim it up later.
5. Once you get to the top slat, stop cutting!
6. The other tricky part of this is the bars that hold the grill and the emblem oval, to the top slat of the grill. If you have a big enough circular blade, you'll be able to cut through it horizontally, if not, you'll have to change bits and grind away at it with a notching bit, it basically will melt its way through. Cut carefuly around the emblem becuase at this point the grill will be a bit wobbly. TAKE YOUR TIME.
7. Once your done with all the cutting the grill will just pop right out. There will be excess plastic on your buhmper, just cut it off carefuly with a razor or knife.
8. As for mesh, just cut out a piece, open up your hood and slide it behine your bumper, if you cut it a little big, it should hold itself right in.
By the way, if you see pics of my car, i had my bumper repainted on the front and before i had the shop repaint it , i cut the grill out, so i had the bumper in my garage detached from my car which made it easier than the first time i did it when it was still on my car. But once i trimed it up and got it painted, it looked great, couldnt even tell that i cut it out.....