I recommend these LEDs.
They are rated at 3v-3.4v, but are plenty bright on the 1.5v board supply, as can be seen in my pictures
If you order the dash led kit from the link that Brad provided above(formerly porscheleds.com), they come with the resistor built in. If you decide to make your own you will need resistors. Likewise, any LED powered off of 12 V(Cigarette lighter, ashtray) will need a resistor. You can use an online LED resistor calculator to determine what resistance you need for each LED.