John,
re the LEDS and which ones to use, have a look at the cointaker site in the USA
http://www.cointaker.com/

it will give advice etc of which LED is used where and why. You can then buy from a local supplier if u want or buy from cointaker etc.
Hope it helps. Thats how i chose the right ones for some of my machines.
Otherwise, alot of members have played with them and can make some reccommendations if need be.  

Cavey