How hard is it to do?
Mine is nasty & I have a white face set up to go in.

 

It is very easy to replace the gauges. Just be careful not to crack the black trim around the cluster. Here is a link on how to change the bulbs in your cluster, but it does tell you how to take it out too.

 

are you talking about the se guage or the indiglo ones? because i know alot of ppl who screwd up their rpm needles accuracy when installing the reverse guages

 

RPM.... or Gas?... RPM needle floats... the gas needle is most delicate in accuracy (I think that's how you spell it)
Anyways when I put my gauges back on, my RPM needle was on the other side of the gauge even below the 8k RPM. I started the car and reved it to 6k, and the needle picked/wined up and went back to the correct RPM.

Anyways it'll take atleast 30-45 minutes to do the replacement/installation for the first time. After you get down all the steps memorized it'll take more like 15-20 minutes to do.

 

put in new bulbs while you are in there, when I took mine out last time I didn't feel like it, and now I really want blue dials ... so I'm doing it again ...

 

I wouldn't recommend using colored bulbs, most of the time after they get warmed up (bulbs) they'll just slowly eat up the potency of the color making it look more like a light blue than dark blue.