Morley Power Wah - adding a status on-off LED

[fin]

I own an old Morley power wah. For some reason Morley in their wisdom omitted a status LED next to the stomp switch.
I have opened it up and have replaced the 2PDT stomp switch with a 3PDT but now am a bit stuck as what to do next.
I tried to tap the +- off the 9v PSU plug but it doesn't seem to light up the LED - I have a 1k resistor on the led - I can get it to light up using a 9v battery but not from anywhere on the Morley circuit.
The new switch is working as it should I just want to also have a visual indication of when the circuit is enabled.
Any help would be much appreciated.

[MikeA]

Welcome!
The first drawing on this page shows a typical way of wiring an LED to a 3PDT foot switch.  +9V/current limiting resistor/LED on one contact, ground on the other.
  http://www.muzique.com/lab/led.htm 
In this case, the circuit is active when the middle contacts are swung north, and bypassed when they're swung south, so the LED lights up when the circuit is active, and is dark when it's bypassed.  The 4.7k resistor value is an example, you can choose your own resistor for desired brightness, 1k is a good start.

[antonis]

Welcome also..

In case you're confused a bit, implement following wiring..