I got my LEDs bulbs from superbrightleds.com yesterday and have all the bulbs replaced that light up when the parking lights are on. One problem I had was the rear parking/tail lights. I had to pull the (67-x9 LED bulb - type 1156 base) bulb apart to swap and resolder the inside connections. All the other lights were wedge type and just require to turn it around.
Our boxster tail light assembly apply the positive voltage to the side and negative/ground to the bottom of the bulb. Regular bulb don't care how it gets the voltage, but the LED bulbs are polarized and requires to be the opposite. If you pull out the tail light assembly out, you will see why it was easier to mod the LED bulb.
I also did the interior and license plate lights like maxferran pics. I got the brighter (WLED-x5 LED Wide Angle LED bulb) for the dome light and they look great. Also replace the inside the trunk light too.
And the (H7-WHP DRL LED bulb H7 Type Daytime Running Lamp replacement bulb with High Power 1 Watt White LED) are not bright enough for anything. I was hoping to replace the foglights with it. Since I have the HID kit for my regular headlights.
Next, the dash lights and maybe the brake lights, reverse and turn signals.
No real benefits other than looks. LEDs are just COOL!
Jay