98 Explorer shock absorbers

It's time to change the shocks on my wife's Explorer. The front ones look pretty straightforward. However, there doesn't seem to be any flats on the top connecting bolts for the rear shocks. How does one go about getting those loose?

Also, any suggestions on how many miles the serpentine (fan) belt is good for?

I think they are studs pressed into the rear shocks the nuts should come off. You should get new bolts and nuts with the shocks. As far as the belt look at the ribbed face on it if you see a bunch of cracks in it replace it.