Thought my audio install might help others in planning or installing their own gear for the MPS6 with BOSE. I am going to mount 2 amps in the boot, change the BOSE subwoofer to a 12" (in the same location), and install 6" components in the front doors. I will retain the head unit.
I haven't purchased all the gear yet but I have started on the wiring. I'll keep updating this thread as I go.
Part 1 - Fuse and connection to battery.
A lot of the parts you need will come in a 4G wiring kit (with exception to the heat shrink).
End Result: (I was going to take photos of each step but totally forgot sorry!)
Tomorrow I will be putting the power cable through the grommet in the firewall.