Which year SC? Early differs a bit from late, as an example.
I have a '90 Sc, and the last time I did mine the hardest part was getting past the plastic shield. The nut is dealt with depending on the assortment of tools at your disposal and the size of your hands. The harness routing needs a bit of attention as well as being careful to not abuse the connectors. I set the gap by eye, not that there was a lot of play to worry about. Overall, I don't recall it being a complex procedure once I had the correct replacement.
What are the symptoms that make you think your's needs replacement?