The car is a bigger problem than the
boat. Unless you are a very early riser each day and can entertain yourself until the show opens parking is a pain. Eastport Elementary
School ($20/day last year I think) is the best bet for most people.
I recommend getting down here by late Tuesday and
anchor in Back Creek. There are lots of parking options and you can get a
water taxi (or dinghy) to the show.
If you really want a
mooring ball your options are the 5 balls in Back Creek, the half of the main field that is open during
boat show, or the balls well up Spa Creek above the bridge. The small field in St Mary's Cove above the bridge is limited to 35' but there are balls for bigger boats further upstream.
There are
Navy moorings in Weems Creek some people use but the
maintenance is spotty and the locals watch people dragging the Navy's "hurricane" moorings around from time to time.
Other than the three creeks I've mentioned there really aren't moorings near
Annapolis. You would have to
anchor. The challenge then becomes finding a place with shore access to your car and then dealing with parking. There are some
anchorages up South River that
work but that really isn't convenient.
Why a car at all? Skip it, anchor in Back Creek, and enjoy Annapolis.