Start on the left(firewall) side and pull that one up and loose. The next three have locks on them. A little black tab on top behind the grey lever. Push the lock down and cam the lever back towards the firewall and lift the connector free. Repeat for connectors three and four. Number five is another wiggle and pull free connector. Then you can move all the cables out of the way and extract the ECU straight up. It is in firmly and you may need a flat blade screwdriver to lift it to get started.

You should have an ESD safe bag to put it in when you get it out. Like computer boards come in.

Have fun..