Rewiring, Should I go ISIS multiplex or "old school analogue?" Options

[phillstek]

As the respray on my car approaches completion it is time to consider what to do about the wiring. Here is a bit of background info that may be relevant.

The car was converted to rhd back in 1988. Part of the conversion involved extending the harness from the fuse box to the instruments, switches and ignition and pulling it over from the left to the right side of the dash. It was always dodgy and I've had a couple close calls with electrical fires as well. The rest of the wiring is original to a certain degree although a lot of the connectors are green/corroded looking. The fuel tank sender plug is cracked and a few wires hang loose here and there. There are relays that don't appear to do anything at all etc etc.

Essentially, I don't want to risk any further incidents and have decided to get the car completely rewired from scratch.

I've had some quotes for a traditional job but for not much more, I can have it done with the ISIS.

I'm leaning heavily towards the ISIS.

Does anyone want to tell me why I shouldn't use it and why I should stay with the old school wiring.

Thanks,

Phil

[McMark]

It just doesn't seem like the ISIS saves you much, especially when you factor in cost and installation time. Maybe if we had more complicated wiring, or our cars were bigger. The ISIS system doesn't change the number of wires to the components (taillights, headlights, engine, gauges, etc) it simply allows you to swap the long runs of multiple wires to a long run of a few small wires. The full harness is around 14 lbs. I highly doubt the overall weight goes down much in our cars. I think you would see more benefit by building a replica harness, but with smaller wires for things like gauge signals (OE uses 18g) and leaving off the sheathing.

Lots of work and lots of money for very little benefit. What am I missing?