I have followed paulsje's instructions to the letter and have completely restored function to the instrument console. The console was taking up to an hour to come on and would usually take at least ten minutes on a restart within a couple of hours. Total cost is pennies for the capacitos from Maplin. Be careful when disconnecting the loom as you can easily scratch the steering wheel and binnacle, think about protecting from scratching with a cloth whilst you are trying to unplug the three main connnectors.
The replacement components are much larer than originals, however there is plenty of space, perhaps with them leant over at 90 degrees. Be very careful about damaging the solder pads on which the capacitors sit.
This has probably saved my beloved LS400 (200,000 miles and sweet as a nut) from the scrappers. Thank you.
