Henry, you are exactly right, it's the concept that has been made clear here and THAT is the most important part. That being you CAN simply pull the spring and put it on. Being with garage made tool like yours, a fan belt, or a chain. It is EASY to install these springs when the method is as we have been talking about, stretch it out and hook it where it belongs.
Lot's of people have tried prying, stretching it out and filling it with nails, I have seen all kinds of ways that are DANGEROUS or damage the paint (nails?) hopefully everyone who pulls this thread open will see that, it's the method that counts not the exact tool used.