Skyjacker kit works well but the finish on the parts I bought from them look really bad fast. I like the James Duff kit I have also. Skyjacker used to be the only one making a 6-8 pitman arm in case you are looking to do a spring over rear. I really like Superlifts long add a leaf and there shocks ride well too.
My 88 BII has a 5.5 Skyjacker lift with long radius arms and the new rear leaf springs. Skyjacker was the only one offering 5.5 leaf spring packs when I purchased. Duff came out with some after that but I don't know if they still make them. Others sell 4" max rear springs and use other means to get to 5.5-6" rear lift. My 94 Explorer now has a Duff 2.5 kit with a Superlift long rear aal. I run 33x10.5x15 on both when I wheel.
BDS, Rough Country and maybe someone else use the plate to drop the stock bracket down. Read where some foks ground down the fins or ribs on the front chunk to clear. Tuff Country, Superlift, Skyjacker, and James Duff kits all have new drop brackets that clear the front center section.