If you mean by instrument lighting the lights in the clock and volt meter, I can't say much. As for the tach, speedo and idiot lights the best thing you can do is install a Katdash system. No more burned out bulbs, no fiddly foil contact patches to fuss with just bright, dependable, fuss free lighting.
As for a LED replacement bulb for the headlight, I wrote a few comments in the MOA forum regarding the light output from many of the replacement bulbs on the market. I chose to upgrade my Bikes with an LED bulb and found as Kurt says, the fan make for a VERY tight fit, some of the bulbs are slightly better but not by much.
The biggest problem was the actual light pattern produce by installing a LED bulb into a reflector and lens designed for a tungsten bulb. Many of the LED bulbs I bought and tried produced weird or very erratic light which was not focused in front of the bike properly. This led to very poor night driving as the pattern in some of the beams was not even but instead was a spot. It could also lead to annoying oncoming drivers at night because the beam produced is not correct as well. As I don't ride after dark anymore, this was not a problem but I still searched all of the hype about replacement LED bulbs hoping to find an answer to the poor beam pattern just in case I got caught out having to ride in the dark.
For some reason I have lost the bookmark to the website my current bulbs came from but the reason I chose these bulbs was due to the video produced by these guys.
https://www.youtube.com/watch?v=nnD_sDWNjEw. They explain all of the issues with LED replacement bulbs and surprisingly when I followed their advice I found bulbs that came close to producing a standard light pattern that was perhaps (I haven't tried it in the dark only against the garage door) acceptable.
As for the LED bulbs, I love the much brighter white color which is much easier to see in the daytime than even the whitest tungsten bulbs. Also the draw on the charging system is much less.
So a long answer, hope it helps. St.