Just an update on the ABS problem.....
There were no handy Nanocoms around, (but thanks for the tip - it's on my Christmas list) so I took it to my local garage (Binnie and Juggins in Needingworth, Cambs - Highly recommended). They found an ABS bleed programme on their generic Fault Code Reader. As it turned out the ABS was returning codes for both rear inlet valves being shorted, amongst other less specific failures. The result of this was that they were unable to do the bleed, but were convinced that sticking ABS valves could create the sinking - pedal symptoms I was experiencing. I got an up-to-date part number from Land Rover (who wanted £1887 plus VAT for a replacement(!!)) and phoned round a couple of recommended ABS specialists; none could help.
I have now removed the ABS completely. Hydraulically I've made up pipes from the front and rear ports on the master cylinder that feed 2 T-piece comnnectors (Available from EuropaSpares or Demon-Tweeks) mounted either side of the clutch pedal mounting. Each of these then feeds the individual wheels, the fronts all the way to the connection with the flexibles under the wheel arches, and the rears to the in-line connectors at the back of the engine bay.
Electrically, I have disconnected the ABS ECU and removed the 30A current limiter from under the drivers seat which powers the pump and relay. I have cut the wire to the TC warning light and connected the ABS warning light to an ignition controlled 12v source. This puts both these lights out. The red brake fail / handbrake light is not so simple. The warning panel logic brings the light on when the voltage on the supply wire goes to (or near) 0v. Best bet is to cut the wire, or bare some insulation, and solder a 1k resistor between the 12v source used earlier and the bare wire. This holds the input at (or near) 12v (light out) unless the handbrake or low fluid switch connects it to earth. In this case the resistance prevents excessive current flow.
My only concern now is that the car is fitted with ABS-specific master cylinder and servo, but no ABS. Does anyone know how the master cylinders differ?
Apart from that, though, a complete success, with the firmest feel to the pedal ever. I've told the insurers, who thanked me for the info, but havn't changed the premium or anything.
I'm in the process of dismantling the old ABS valve housing (I couldn't help myself.....) so if anyone wants pictures or details of this or the wiring mods or plumbing I did, just let me know!