1980 DOD440 LED Install

[TyeDye]

I recently managed to get my hands on a 1980's DOD440 and I want to install an LED.  I know many will say not to mess with something "vintage" but that doesn't really matter to me.  I like the sound of this pedal and it's practical for me to have an LED on it.  It's just a metal box and it is the sound I care about, not the aesthetic of metal box (it already has marker on it from a previous owner anyways).

That being said, I am a complete noob to pedal modifications.  I have changed the pickups in a Telecaster and that is the extent of my experience with guitar mods.
Almost all LED install tutorials I have seen call for a switch to a 3PDT switch.  If I install a 3PDT, will it change the tone of the pedal much?

I've been wanting to take it to someone professional, but I can't seem to find anyone in my city.

ps. I wanted to upload a picture but I'm such a newbie I'm not even sure how to do that

[mcknib]

A 3PDT is needed for it's 3rd pole which is used for the LED switching the other 2 being used for inputs and outputs, it shouldn't affect the actual circuit tone aside from maybe the switch popping when you switch it on with the absence of a pull down resistor which you can easily install at the input to ground using a 1M resistor.


Have a look at http://www.generalguitargadgets.com/pdf/ggg_ef440_lo.pdf to give you some idea this is their 440 replica which uses a 3PDT and as you can see has an LED indicator and a 1M5 pull down resistor (R18) at the input.

All other docs for this project are here http://www.generalguitargadgets.com/effects-projects/filters-envelope/dod-440-ef/

Just hit the picture icon when you post to upload images and insert the image url your images will need to be uploaded to the web to somewhere like imageshack