Clutch cable replacement help

[Ray Sta.Juana]

Ok, so I'm reading my Chilton manual and it seemed simple enough. Loosen the
?wingnut? and disconnect from tranny, then disconnect from clutch pedal then
remove two bolts from the firewall and you're done. So I look and there's no
way I can get a wrench to one of the bolts on the firewall with this thing
(no idea what it is) in the way. Any help would be great as I don't know if
I should take it off, move it out of the way or there's some sort of trick
to doing this procedure easier. Thanks a bundle.

Ray S
98 Sentra SE