[Mark Ayers]

set the points at .15 to .17 of an inch. this is pretty close to a 30deg dwell and you should be in the ball park. a set of feeler gages should work failrly well. As far as them being run off the flywheel, then their must be a way of setting them with it on, or like you say a weird special tool, but I’m inclined to think that volvo would have a way to access the setting with the flywheel on.
Mark