Ed,
A possible solution would be to park your Westy at or near one of the many train stations scattered about North and Central Jersey and take the train into the Big City.  What with the carpooling restrictions that are presently in place, you may not even be able to get the bus into the city in the first place - though, admittedly, I don't know if those restrictions will be in effect on a Saturday.

The trade-off is the security of your bus.  Parking garage or train station lot, either one could result in damage one way or another.  Those garages are not all that secure either, come to think of it.  

My $.02...

Alan Bosch
& Phred ('88 Wolfsburg)