Mitsubishi A2C Controller How to connect to scada

Hello, I`m having problem with a system which use a Mitsubishi A2C controller with few I/O module. I need to connect this system to a scada computer running intouch and the RS-422 port is being used by a E-300 operator interface. I know the E-300 has a transparent mode which means I can read and write programming ladder going over RS-232 and then to A2C controller. I am wonder if I can use this way to connect my Intouch aplication. Other way could be, At last rack extension the system has 3 free slots which I am planning to use with an A1SJ71E71N-T and with this conection I can use an OPC server to pull data from controller. Can anybody help?

either use the ethernet or a serial card. serial being cheaper but slower.
Its very easy to attach an OPC server to either, Kepware, Takebishi OPC servers work well.

Have you connect a compurer between A2C controller and an E-300 operator terminal in seria RS-422 channel for pulling data? for example if the A2C controller were address 00 the E-300 address 01 and the PC were address 02, connecte in the same serial cable (link). Do you think Melsec IO server from Intouch will talk to the A2C controller? The E-300 will keep working fine? I know there ai an controller A2CCPU24C which has an extra port so I can use this but I`m trying avoid bying another controller.