A few days ago, I started bearing noise (like air being released) from the general area of the auxillary belt. As it's freezing outside, I booked it into the garage and hoped it could make it the few days until the garage could see it.
Inevitably, it didn't. After starting the battery warning light came on, and as the belt was still on I checked the battery voltage - 11v and dropping, goodbye alternator bearing...
This documentation details the steps necessary to swap out the alternator on a 2003 Volvo S60 with a Diesel engine. The steps differ slightly for later years (you need to remove the radiator cooling fan to make space to get the alternator out, but can simply move the P/S pump out of the way rather than disconnecting it), but should be applicable for vehicles <= 2003. From what I've seen, it should also apply to V70's of the same age.
Some of the images are a little blurry because the weather was getting ready to snow on me, so there was quite a bit of shivering involved.
The whole process shouldn't take you more than a couple of hours, unless you have to wait for replacement parts to arrive.