However if you must work on the things , getting the return springs off and on is one of the challenges.
A "recycled" pair of side cutters makes this job much easier ( and safer ). Simply drill a hole in the sidecutters cutting edges of suitable diameter to clear the springs wire dia. and around 3mm from the point.
This allows you to grasp the spring in the hole in the edge and apply whatever pressure is necessary to disengage / engage the offending spring. As the cutting edges are biased towards one side you can also get in very close to the brake shoe.
It doesn't matter how blunt the sidecutters are as your not using the cutting edge, so old ones are perfect - just make sure the grips dont slide off
