Address 2 different Midi controllers to 2 different instruments: How?

I have to contemporary trigger (and record) 2 different Midi tracks for 2 different plug-in instances: Sperior Drum 2.0 and Ivory. My Roland TD3 (conncected to AMT8 Midi-port n. 5 In) is the Midi controller for S2.0, whilst my Fatar 900 Studio Keyboard (connected to AMT8 Midi-port n.6 In) is the Midi controller for Ivory. The problem is that on Logic I'm not able to address TD3 to S2.0 and Fatar Keyboard to Ivory. Both the controllers trigger both the plugs (obviously if I enable them on arrange). What I have to do?