The pin on the master link should be about 1mm wider than the other links (typically 12mm). Bend the chain sideways to reduce the distance between the pin ends and pull the plate off the link. I do stock inch-pitch chains for $75.00 each.
I don't believe in wall hanger bikes. With all the Ukuleles on my wall my wife would never allowed bikes too. When it comes to bikes, if I can't ride them I don't want them.
Kevin Casey
Encino Cyclery