i don't know if g4 led's are any different than a usual one, but standard and super bright led's on their own tend to be put with 220 ohm resistors, however if you have 3 in series with each other a resistor is not needed
hope thats some help & good luck, looking forward to seeing some photos
here is my reasoning, wiring leds in a series does not allow full current to reach the leds so the first led is bright but the ones following are subsequently duller. Go with wiring them in parallel. most standard leds even super brights require a forward current of around 3.3 volts, and a draw of 25milliamps, wiring these in parallel will allow you to run them off a 9volt battery, with only 67ohm resistors if your doing 4 in parallel. (one 47 ohm and one 22 ohm soldiered together).
i had to do major wiring for two costumes in one week, if you need any help let me know.