Parts required:

PP3 battery & clip
1k5 1/2 watt resister
LED (light emitting diode)Any colour about 20m/a current rating.
Small ABS box (size to fit PP3 battery + a bit for other parts)
Were it says see text these are 2x 4BA round head nuts and bolts,you will require 2x tab washers.
to connect wires on to.

Assembly

On box lid,drill hole for LED. Drill 2 holes about 20mm apart for bolts (head side up).Drill hole (5mm) to fit LED and drill holes for Bolts + their nuts and tab washers. Connect the RED wire from the PP3 clip to one end of the 1k5 resister and the other end to one of the tab washers, connect the other tab washer via a piece of thin wire (or the long lead of the LED) to the LED. Connect the BLACK wire from the PP3 clip to the short lead (cathode) of the LED usually denoted by a "flat" on one side of the LED. connect battery and place a good fuse across the 2 cheese headed bolts,LED should light up. If it does not work! check wiring, and if OK try reversing the connections to the LED, you cant damage it.

Suggested supplier. MAPLIN ELECTRONICS
PP3 clip. part No.HF28F
Box ABS. part No. WY03D
Resistor. part No. M1k5
LED green part. No. CZ26D
Tags 4BA. part No. LR63T
Bolts. part No. BF03D
Nuts part No. BF17T