I just did struts (and shocks) last fall. On the struts, the parts consist of mount, bushing, strut and lower mounting hardware. It would be silly to not replace the bushings (also called spring seats), do that. I polled for recommendations and decided as long as the strut was off, I'd replace the mounts too, even though they weren't broken. You can get them for $75 each at fcpgroton (see below). I did not replace the mounting hardware. these links are useful:

front struts:
http://members.shaw.ca/heeeeee/strut/
but beware he reversed the part numbers for strut-to-steering-knuckle nuts and strut-upper-mounting nuts.

rear shocks:
http://www.volvospeed.com/volvo_performance.php
then scroll down to "Bilstein shocks" link. The rears are really easy but this was useful.

Haynes manual was useful but has some extraneous stuff about spacers that didn't exist on my car. It is necessary to do a wheel alignment when finished because the strut upper mounting nuts are adjustable (sliding mounts).

cheapest parts, plus they are useful phone consultants (like IPD without the hype):
http://fcpgroton.com/

Dogma on replacement suspension parts, softest to firmest:
Sachs OEM < Boge < Bilstein "touring" = "economy" < Koni < Bilstein Heavy Duty

good luck
--
96 850 wagon