May be I'm getting a bit too involved in this wiring business but I've gone for some gucci gucci fake fabric-like heat shrink
(Apologies for the picture - snow on the roof of the workshop today made everything dull so the flash on the camera activated which makes everything look a bit anemic)
It gives the wiring loom a bit of an olde worlde feel.
Most importantly despite the extra thick wiring and the extra number of wires the heat shrunk cables for the front section of the car go nicely through the original hole in the bulkhead
...Now I've gorra find that PV rubber bung kit I bought