I replaced all 4 of mine at the same time, that was a rough day! The uppers are actually easier than the lowers, leave them bolted to the control arm, unbolt the sway bar end link and shock to get some slack, take the big nut off (mine was easy to get to?) and stick a pickle fork on there and wack it good then take off the 4 nuts and remove it.

1986 4X4, 1991 22RE, 5.71 gears,ARB Rear, aux fuel tank, 3mm O/S TB/intake, engnbldr cam, LCE header, magnaflow w/2.25 exh. custom 4 color paint job :-P 33X12.5 Goodyear MT/Rs