NEWBIE WARNING! Impatient people, turn away!

Ok, coin door questions could be associated with just about anything on this site, but since mine is on a Creature pinball, I thought it fit here.
The coin mech on my CFTBL pinball takes French Franc coins. Being a stupid american, I don't know what the size difference is between than and a U.S. quarter.
Also, if I post pics in the thread, would someone be able to tell me if it is adjustable to take Quarters?
Thanks.
Ultrageek
"There is no knowledge that is not power."