Thanks for replies, silky me forgot to put in OP I have sheilded cable for vr sensor, all new plugs for injectors and temp sensors.
I have a background in electronics/electrical so all joins, splices etc will be soldered and wrapped in heat shrink, I have the harness tape on its way.
Great idea Nigel regarding the waterproof box.
Lots of zip ties already in use for temp harness restraints
Tacho output on ecu?? Is this possible as my RR use the alternator fir the tacho feed? (Would be great if it is possible)
Thanks
John