Thanks Bill that'll be useful. Looking for a supplier I came across this chart on the Galfer site which may be useful to others too - for me a picture is worth way more than 1000 words!
I've tried searching for those pads, but they are not easy to find. If possible could you please post a link or say where you got them from. Doh, I've just seen that you are in the USofA so if anyone has a UK/EU based supplier link could you please oblige.
Thanks, Gren