Finally fitted the Sub, that I ordered a few weeks
ago, to try and improve the standard install's lack
of low end.
To keep the space usage down, got one of these:
Unit switches on when it detects a signal at the high speaker inputs.
Bought an ISO DIN speaker socket with bare leads
and also screw fit ISO DIN speaker plug to create
a patch cable.
Connected this to the High/Speaker inputs (for the rear
speakers) at the back of the head unit. (Without having
to cut into the loom.
Ran the cable back alone the centre console.
(One bit still needs to be hidden.)
Power was obtained by removing the parcel shelf,
unscrewing the LHS shelf mount and detaching the
rear fuse box. Nice big always-on +ve available
from the unused fuse holders.
Ground was easily available from a LHS rear light cluster
bolt. (Once I gone and bought an offset 10mm ring spanner.)
Unit was then screwed to the back of the LHS rear
passenger seat. (Need to use shorter screws than those
Job done. Not the sharpest piece of kit, but small, black
and fills in the missing bass from the standard rear set-up.