... and removing the C-clip means taking the diff housing off the traction beam. Not at all rocket science (you won't be touching the gears so you don't need to worry about installing them correctly). But it's not a 5 minute job either.
But older diffs have a retainer that bolts on from the outside, so make sure you don't have that first. It would be a drag to go to the work of removing the diff from the vehicle only to find that you just need to unbolt the retainer.
Bob
Sorry, no '80 - '86 Ford trucks
"Oswald": 1997 F-250HD crew cab short box, 460, E4OD, 4.10 gears
"Pluto": 1971 Bronco, 302, NV3550 5 speed, Atlas 4.3:1 transfer case, 33" tires
"the motorhome": 2015 E-450-based 28' class C motorhome, 6.8L V-10
"the Dodge": 2007 Dodge 2500, 6.7L Cummins