Just the one.
Weirdly, I had to shave down my new wheel cylinder with a dremel tool to get it to fit,even though it’s an AC Delco “professional”part . No pictures (I forgot) but I’ll post it when I do the other side, . Those assholes.
Apparently the trick to these is to have a third arm, or a helping hand. I struggled with the self adjust because the arm has 2 pieces, 2 springs, and a linkage all to juggle with. Luckily my dad works from home.
Lastly, I think these tires may be a bit dry rotted