Using the floor jack, I was able to relieve the pressure on the leaf spring and with several blows from the hammer, the passenger side shackle came apart. What I found when I went to install the new grease seal was that the bottom shackle pin could be wobbled in the bushing. Upon closer inspection, both the bushing and pin were damaged. The bushing was actually missing a piece and the pin was severely worn. I've attached a pic of the pin. So, I'm in for a complete rebuild, not just new seals. Not too surprising, I guess.
For those who are going to do the same repair, I found that it took very little upward pressure from the floor jack to allow for disassembly of the shackle. Your mileage may vary.
