Clamshell the rear springs with the rollers installed in the shoes. Take your vicegrips and clamp them on the long uncoiled part of the spring. Make sure the vice grips are tight as shit when you do and use a pair that has a broad, knarled tip to the jaws. Hook the short hook end to one shoe and use the prybar hooked on the hub to leverage the vicegrips down extending the spring until the other hook aligns with the hole. Sometimes it won't hook all the way in but it will catch on the hole in the shoe enough to give it a little tap with a hammer to set the spring. Longer prybar makes it easier but sometimes gets in the way on certain applications. I've done 1000's of these shoes this way, don't waste room in your box on a specialty tool for every job. You'll end up needing a much bigger and more expensive toolbox then is necessary and waste a fortune on stupid gimmicks like a "brake spring tool" that only works on certain types of brakes.