Hmm.. well I am not really sure about the factory system, I would doubt you would find all the wires you need in one location/harness usually not that easy.
Just keyless entry is not all that bad on most vehicles, on an 80 there are a few tricky items.
I will just tell you what's involved, and you can be the judge on if you would like to attempt it.
You will need 12v constant, ground, ign (if you want to utilize some kind of auto lock unlock feature)
and then the lock wires (3 in this case)
12v constant- Most of my books show that a constant 12v source is not available at the column, I think this really means, do not access it there because circuit is already maxed out. I highly recommend a separate wire to the battery, with a fuse within a foot of the battery. Safe, easy, no chance of tapping incorrect wires.
ground- good solid metal point, paint removed, good ring connector and lock washer, screwed down securely
ign. - can be accessed at ign. sw area-check with test light-black/red wire on a 96
locks-here's where it gets tricky. wires located in drivers kick panel/8 pin plug.
lock- green/red
unlock-blue/yellow
**toyota child safety lock wire** blue/orange
this will be hard to explain, but a relay is needed with the unlock output of keyless being split to unlock and child safety wires, with diodes inline as ALIA mentioned.
I could fax/mail you diagrams and wire colors if you would like. Otherwise I would think most Car Audio shops would do this for $125-$200 on average. Verify their skill levels and warranty, if they say they have worked on tons of landrovers while staring at your LandCruiser , walk away......
hope that helps...
