As far as I know the only thing you need to be aware of when installing LED's are the fact that they are polarity sensitive. Meaning if you don't install them correctly they won't do their funky thing. As you won't be using them as indicators you shouldn't need to have a load resistor fitted to them or an electronic relay as they draw such a low amount of current. You know when someone has installed LED's for indicators and haven't put a load module onto the circuit - they blink like christmas tree lights lol

...whoa, just had a thought while putting this post up - will LED's in the indicator dash lights mess with the indicator relay?