Well it's not on my PC, I didn't think it was, so it's on paper somewhere.
Alternatively you could splice your lockup toggle switch ground into the O/D ground wire to the PCM. That way when the trans comes out of O/D it will unlock the converter as well. I would run it through a relay though just to be sure you don't burn the driver out in the PCM. Blue wire is ignition hot, orange with tracer (blue or white, I forget which and I'm color blind so keep that in mind
) is the ground.
Edit; the O/D kicks out at about 30 mph which is too low for the L/U clutch to be on, but it would at least unlock it before the trans downshifts into 1st.