Disconnect the battery first.
Open the alu box under the bonnet (on the left on RHD and vice_versa) remove the first electronic box (car electronic harness and bus) it is just velcro.
If in the way ( I don't remember) unscrew the multi relay support.
Then remove the ECU, velcro also and remove the 2 connector by moving the 2 lever.
You can find all schema for various model here : https://mogparts.net/parts-guide
Enjoy the map upgrade it make a real difference (even without the sport exhaust.
drive