I have done plently of knock sensors in the past. 95, 97, 98's and always had easy access to them, and got them done within 20 minutes. I went to go change mine on the 99 I have now and it seems like it's much harder to get to. Looks like there are more wiring harnesses going past that opening. I generally hate doing knock sensors, but this time I almost don't want to touch it!

 

I think the big difference is wether it is a cali spec or not. Even after I took out my swirl valve it was very difficult to change it.