Finally got around to installing the Spicer rear diff cover this morning.
Snapped three bolts off, so that was plenty fun. The one on the bottom was definitely the most difficult, I slowly worked up to a 3/16" drill bit plus some heat and a
lot of persuasion to get the thing out. The top two were surprisingly not too horrible. A lot of patience was involved for all three, but it worked out. I used the ARP bolts that have been mentioned around here, a lubelocker gasket and Amsoil 75w-90. Torqued to 33 ft-lb. I'll be doing the front with another Spicer cover, but that might be awhile.
I also drained and filled the transfer case and changed spark plugs. I used the SP594s. At 43k, I didn't think they looked too bad, but the new ones got some anti-seize.
I also hit the underside with the B'laster Surface Shield last week. We'll see how it holds up this winter. On a final note I wanted to mention that the buzzing I was hearing from my new-to-me shocks I installed last month finally went away. I'm wondering if it went away after the truck settled from when I installed the Icon leaf springs.