reason the horn doesn't work is prob down to the wiring...
what you have to understand half of the stuff in there could be for things you wouldn't ever consider being in a car...
in japan they have toll gate electronic pass machines, so instead of slowing down and stopping to pay, they have a unit in the car that has credit on that they can just drive through a toll.
also a lot of cars that come over, ALOT of parts get robbed at the docs by people, so this might of had a turbo timer, gauges etc and they get removed at the docs in japan and even on the ships, if its a roll on roll off.
when it comes to fitting low current drawing things like the above they get slapped in with scotch locks, even though they are a complete c**t, the jap scotch locks are a lot better than what is used in the uk!
gaz, if you are really stuck and fancy a weekend or a couple days down south, bring it to me, I'm working with a mate who owns a tuning company now he is a rx7 specialist, i will take a day or 2 off and help you for free
can even crash at mine if you need to.