Hey PStickney
While the PB2Y was designed to have level bombing capability, it was not with the 1600 lb AP - at least not unless the bomb it was intended to drop lagged behind in development by 4-6 years. The 1600 lb AP did not enter service until 1943 (I think). I may be misremembering, but I do not think the US had a proper AP bomb bigger than 500 lbs(?) in service before the war.
Also, although there are many inspirational stories (propaganda) saying otherwise, after pre-war testing of the Norden bomb sight by the Navy, it was determined by the Navy that it was virtually impossible to hit a stationary capital ship sized target from more than about 10,000 ft when level bombing.
You're pretty much correct - I was running from memory, and got things a bit muddled.
The 1600# AP did exist prewar - it's included in the June 1942 TM9-1980 "Bombs for Aircraft".
But, the PB2Y didn't carry it - checking the Pilot's Handbook, the wing cells/bays were sized for the 1000# AP. in the prewar series. It seems it could also carry torpedoes - either 4 Mk 13 aerial torps, or (astonishingly) 4 Mk 15 heavyweight destroyer torpedoes. I haven't seen any reference to any air-dropped Mk 15s before this. The idea of a PB2Y making a torpedo run is mind boggling.
In addition, there were a number of odd-sized AP bombs, which appear to be 12" and 14" battleship AP shells fitted with carrying lugs and tails.
I'd like to see the reference for the Navy evaluation - the initial intention was that ships would be attacked by pattern bombing from a formation of bombers, and thus saturating the error circle.
In the event, though, that tactic was never actually implemented - in the early days, there were too few high altitude bombers in the Pacific, and carrier aircraft - Dive Bombers, and, after the issues with dropping the Mk 13 were sorted out, Torpedo Bombers proved more than capable of doing the job.