Passive A/B Switcher Question

[lebo]

I found instructions for a Passive A/B switcher at fulltone.com  http://fulltone.com/qaframe.html .  There are, however, a couple things I'm not sure about.
1) It says that all the parts should be available at mouser.  At mouser.com it  says that the yellow LED (part# 604-L53YD) is an obsolete part.  What type of LED should I get instead?
2) Out of curiosity, why is it that the Red LED needs a 10K resistor and the Yellow LED gets a 2.2K resistor?  Is it because the different color LEDs needs different resistors or is it because of where they are in the circuit?
3)Finally, any opinion about carbon comp/film resistors vs. metal film resistors?  Not sure if it really makes a difference in this application.
Thanks

[Barcode80]

different LED colors are rated to be able to handle different voltages. so, if you take two diff. colored LEDs, they each need a different valued resistor to keep them from blowing out.

radio shack carries yellow LED's fairly cheap. any 5mm yellow LED that does not have a *clear* housing will work. LEDs are not really a project specific part usually, unless used as a clipping stage. at least not in the sense that mouser part numbers matter just save the hassle and hit the ratshack. in the future, i would suggest ordering LEDs and such very common parts from smallbear (www.smallbearelec.com) or Aron (www.diystompboxes.com/cart/) or pedalpartsplus (www.pedalpartsplus.com). Much easier and you can talk to them directly if you have a question about a part. Aron runs this place, so he is always here, and I Steve from smallbear is a member, posting from time to time.

FYI, i prefer blue, white, and ultraviolet LEDs, all available at ppp or smallbear.