aikischmid
The headlight wires on your UCE are as follows:
Amber = ground
Blue = High beam
Green = Low beam
These show up nicely in bare's picture that he posted above.
The real problem now is to figure out which wire is what the red, green and white wires on your headlight are. If I had to guess, the white would be ground but this needs to be verified.
The best way to do this is with a volt/ohm meter. (Having one of these is a good idea anyway what with all of the little gremlins that exist in an Enfields wiring harness).
I found a real cheap one at Harbor Freight. I think it cost about $3.00.
I also bought a really good one at Sears for about $20.
If you have one, set it to read OHMs and touch its probes together. The meter should read 0.000 (zero). Be sure to check this to make sure the meter is working.
Now, touch one of the probes to the white wire and the other to the red wire. If there is NO reading you will know that NEITHER of these wires are the common GROUND wire.
If you get a reading write the number down. You also now know that ONE of the wires is the ground wire.
Now, touch the probes to the white and the green wire.
If you get a reading, write the number down. You now also know that the white wire is common to both the high and low beam because it was connected to both of the other wires. This reaffirms that the white wire is the ground wire.
If you get a reading with the white/green combination but you did NOT get a reading with the white/red combination that means the Green wire is the common GROUND wire and you must repeat the first test using the Red/ Green wires and write down the number.
After you have the numbers you can compare them. They should be quite different.
The number (of ohms resistance) that is smaller is the HIGH beam.
The number that is larger is the LOW beam.
For example, let's say the white wire was the common Ground wire because it worked with both of the other wires to give a resistance reading.
Lets say the Green/White reading was 4.36 and the Red/White reading was 2.22.
The larger Green/White is the LOW beam and the smaller Red/White is the HIGH beam.
With this knowledge added to the harness wire colors the White wire would connect to the harness Amber wire. The Green wire would connect to the harness Green wire and the Red wire would connect to the harness Blue wire.
This sorting out which wire is what can be done without an OHM/VOLT meter by using two wires connected to your bikes battery for power and then connecting them to the wire combination's I mentioned above but you will visually have to try to figure out which combination gives the brighter light to know which wiring combinations are the High and Low beam.
Have fun.