Another quick update on the completed job, the earth strap disintegrated as soon as I disconnected it, so cut back the corroded braiding using a junior hacksaw, and used two cheap earth straps from another vehicle found on EBAY, to attach the main earth to the chassis, it’s not to clear in the photos but the main earth runs from behind the suspension strut/airbag and is very difficult to trace, anyway started first time, a great result.
The hardest part was wrestling with the wheel arch liner and front wheel arch trim as they both need to come off, to get to the earth strap, more than 10 wheel arch push clips and several screws holding it in place, didn’t worry too much about damaging the push clips, as they are very cheap to replace and easy to fit, hope this is useful.