The connectors on the standard lights are a "mini spade lug" type and have positive and negative wires. The silver bullets have a single wire with no connector, and are earthed through their bodies, however the earth connection inside the light can be disconnected and you can put a seperate earth wire on instead if you need/want to.
If I understand you correctly you want to completely remove the standard turn signals from the number plate mount, and have the silver bullets mounted on the sides of the rear fender? If so you can use the fender as an earth and just connect the bullet's wire to the bike's positive wire. I used "scotchlock" connectors to connect the wires (which preserves the original connector without forcing you to find a matching one for the bullet) and hid them behind the number plate, and insulated the original connectors with heatshrink tubing so they couldn't accidentally short out against the number plate etc.
If you're planning on doing it this way there's two different types of silver bullets. One has the wire coming out of the body behind the mounting bolt, and the other has a larger hollow mounting bolt with the wire exiting there. Using that larger one will allow you to keep the wiring hidden under the rear fender. You'll also want to purchase the "metric adapter kit" as this'll let you do a neater mount. Finish it off by finding some dome-head bolts to fill the original turn signal mounting holes in the number plate mount. (You can either paint them black or get chrome ones to match your mount as required.)
I'm not at home right now, but if you want I can post pics of mine when I get back.
