I'm sure it is even a big job for a Volvo trained Tech, and he'll likely
expect you to accept around $500.00 for him to do it. Anyway you need to
set your browser to Swedishbricks.com and perhaps check out some
included links and I'm sure they are explicit instructions on how. I
have done 2 blower motor replacments myself on 2 240 series and I'll
tell you this I removed steering wheels and at least drivers seat for
ease of access to many screws and removing dashboard out completely, I
dunno for sure if all this removing was absolutely necessary but I have
a bad back. I would recommend a new blower motor while you're in there,
you don't ever want to do it again, trust me on that.
Good luck,
ps mark where all wires where they were attached or you will be posting
for ever asking what goes where! maybe use a digital camera before
disconnecting the numerous plus and wires.