hi toonarf, if your still having issues with the doors i can confirm i fixed mine with the springs cost me less than a fiver from ebay for a set of 5 (all doors and tail door). there's an awesome guide on here explaining how to do it and it was a lot easier than i thought it would be, my only warning would be be careful of the plastic clips on the backs of the lock barrels when removing the linkages. if like me you happen to snap one there £13 on paddockspares.com.
additional info on what i've done since this thread started,
rev counter fixed - simply cut the connector spade off the wire on back of alternator and replaced it with a new one.
window unit soldered but not fixed, also switches were a bit dodgy so i've stripped and cleaned them now there all good i'll be putting up a guide with images later for cleaning the switches.
speedo is a little crazy trying to work on that now but i did change the transducer, old one came off in bits again easy job but a little tricky to get the rite angle to get your hands where you need them
not repair or landy as such related but i also fitted USB charging ports each side of the clock surround on ignition live. handy for my phone one side and anything else (satnav, passenger phone, mp3 player) on the other side.
