Just rewired my series 2 fitted with a 2.5 petrol and alternator. Did not want to fit off the shelf loom as I would be making many alterations so I bought a new loom off ebay that the seller did not know what model it was off , this I completely stripped out so I could use the proper coloured wires but I fitted 2 fuse boxes and relays for headlights. The bulkhead to rear loom was made using 7 core towing cable. Very easy to do if you take your time and have good quality crimping pliers,and plenty of connectors. Wrap loom only when you have finished running all wires and tested everything. Unwrapping a length of new loom to add another wire is a real bind, as I found out the hard way.