I can see my cruise control solenoids after removing the front, right fender liner, but I am not comfortable attempting to remove them without messing something up. Has anyone ever successfully accomplished this task? Thanks. 1997 XK8 convertible, non supercharged, LHD.

 

Yes, people do replace XK8 cruise control solenoids from that access, but it’s fiddly. The main challenges: tight space, delicate throttle linkage, vacuum lines, and connectors.
If you aren’t comfortable, professional help is strongly recommended.