Caliper bolts are torqued a bit close to yield using loctite, hence the recommended bolt replacement in case they were ever over-tightened. Few people or shops bother to replace the bolts. Few people bother with the recommended loctite, either.

I've never heard of a caliper coming loose if the bolts were half properly tightened. Still, I recommend properly torquing them and I always do. Main thing is not to get carried away and overtorque a previously used bolt closer to the failure point.

Volvo torque specs should be something like:

240 Front caliper bolts 100 Nm, 74 ft-lbs, 890 in-lbs
Rear caliper bolts 60 Nm, 46 ft-lbs, 535 in-lbs

700/900 Front caliper bolts 110 Nm, 78 ft-lbs, 930 in-lbs
Rear caliper bolts 60 Nm, 46 ft-lbs, 535 in-lbs
Front caliper guide pin bolts 30 Nm, 24 ft-lbs, 270 in-lbs

Careful with bleeder nipples. Huge pain if they break off. If the bleeders haven't been opened in a long while then soak overnight in penetrating oil. Avoid using a 3/8" ratchet, even a 1/4" ratchet, much better off by hand with a box end wrench or flare wrench where you can better sense force and movement. To break the thread seal, if it won't break counter-clockwise then try a little jerk clockwise. Do this with increasing force until it cracks free. Avoid rocking the wrench quickly back and forth as it increases metal fatigue. I often find a gentle tap with a hammer to the wrench to break the thread seal works well if you're careful.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now