UPDATE!

From my trusted mechanic at AAMCO:

#3 & #4 are for the interlock pins for 5th gear and reverse. DO NOT REMOVE! YOU MAY HAVE SOMETHING DROP IN THE TRANS!!!!!!!


Of course I removed #3 as I mentioned, but nothing was moved, and it was promptly replaced. Test drive proved that the Trans is okay, but with a nice fresh bath of fluid.

BTW, this '96 now has 161K on it, and I'm replacing the front Rotors for the first time...not too bad :-)