1 - i used an extensive wrench and had no problems. don't insert your key, so your steering wheel can lock itself, and therefore allow you easier work. when removing the steering wheel, don't forget to give contact so it releases it.
2 - i've put the same kind of gauge cluster (with check control), but different years, the difference was in the position of the airbag and the battery lamps, but everything worked just fine.
3 - bulb was surely to blame if your signal was working, but it didn't light on the gauge cluster. if not that, maybe just a bad contact, try to clean the metal where the bulb aligns with the cluster.
4 - have no idea about auto trans.