Those locks don't pick very easily unless you are *very good* with locks (ie locksmith)
The bic pen trick generally doesn't seem to work very well at all with typical arcade locks, that story circulating was specific to a bike lock.
You got a couple of choices:
1) Try to pick the lock (pen method) - Not likely tho
2) If you can gain access via the rear you can take the lock apart from the inside. This will get you into the coin mech door, but usually the coin bucket area is protected by a metal box. It depends on the cab.
3) Drill the lock out.
4) Pry the door open. Actually, this isn't as bad as it seems. You will bend the door slightly and you will damage the paint alot. If you planned on refinishing the cab anyway, you can usually repair the damage without too much effort.
Good luck
D