Down here you would be told Illustrated Parts list to indicated there was a diagram of some sort , not just a list of parts & numbers .
And yes, if the blower fan has to be removed then most are not an economical repair
Occasionally if I get a newish blower in so I can pull the fan & put some anti sieze on the keyed strait shaft ones they remain repairable.
Most of my customers use the big Stihl blowers & they have all been told unless they pull the fan off, don't bring them in because it can take the better part of a full day to get the fan off.
The shop I get most Stihl parts from smashes the fans &replaces them because that is cheaper than trying to remove them undamaged