The most difficult thing about changing the bulbs was getting the cluster out of the dash. Just take your time in getting the cluster out and you will be ok.
OK, so I suppose the questions has anybody done a writeup on how to get the cluster out? I know there are 4 small bolts on the front edge. How much is there after that?
As Musty wrote just above this post, it is no big deal getting the cluster out. It is some fiddling though. I have the grant wood steering wheel and did not need to take it off, but it was a tight fit.
I had to unplug the alternator socket with the instrument cluster in place as that one is connected to a separate cable. I don't know whether this is stock or not, because some previous owner had messed around behind the dash.
If the cluster doesn't move check this first.
Once you have it out, I recommend some tweaking for maximum gain from the new LEDs.
Check this link, where I posted this info, so I don't need to hijack this thread:
http://www.7173mustangs.com/thread-dark-instrument-lights?pid=11817#pid11817
It's really no big deal, as I was able to pull it off all by myself, without breaking anything or hurting anyone!