The way I did it was to take a manila folder and make a template. Poke the pins through first, then trace around it, then cut it out. The template will conform to the curve with no problem, and get the pins located in the right places. The manila is strong but thin enough to bend on the curved front. Disclaimer: I did this on a Spyder, which is fairly flat.
Also, the template can serve to align the placement. Look at the car from as far away as you can to make sure they're straight.
Use masking tape over the whole area, and start the holes running the drill backwards. Use a small bit, slowly increase the size, and drill slow with LIGHT pressure. It is possible that you may have to grind the backside to get the fasteners to secure, if the glass is very thick. Once they're drilled full-size, seal the raw fiberglass with clear, touch-up color or clear nail polish(don't laugh, it works).
That's what I did, but others have cut the pins off flush and used double-sided tape. If you go that way and cut the tape by hand, I'll recommend Wurth emblem tape. I used that on my VW Corrado after a paint job. To buy new emblems was pretty steep, so I carefully removed the old tape and applied new. With a piece of glass and a #11 Xacto blade you can do a great job cutting the tape. The Wurth tape is thin and black and disappears.