Just to be sure I read you right and you read the instructions right. Regarding the picture of your tool. One of the lower arms in pic is for installing spring (right hand arm in pic) and the other lower arm in pic is for removal (left hand arm in pic).
Left hand barrel is twisted/rotated to release spring from post.(one way for one spring, other way for other spring). Right hand is used to install by attaching one end of spring to shoe and sliding other end of spring down the tool arm and over post by placing arm into spring hook and at the same time placing end of tool (groove) over post and lift and move arm at proper angle to cause spring to slide onto post.
I use the upper two arms to install self adjuster spring. There is a separate tool for the shoe retainers/hold downs.

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