I remember trying to remove a spring off a hood hinge years ago, prying with screw drivers, that is the first thought for most of us, pry it off. Then how do you get it back on, pry it on of course.
Thank God for the "old guys" who know better, I had an old bodyman show me the proper way and I have found this method to not only work on hood springs but many other springs as well. It is all about control, with prying you have ZERO control, damage to you or the car is a given, SOMETHING is going to get damaged.
It's like the difference between pulling on some damaged sheetmetal with a slide hammer, or pulling it with a pogo stick or even frame rack, you have CONTROL and it "walks" out to where you want it.
The trick with the spring is to use your muscle to pull it off the hinge, and believe me, you have enough muscle. That is, IF you have the control. I use the chain off my Pogo stick which has a flat metal hook on it. Do yourself a favor and make one of these, or, just cut the last link in a three foot or length of chain into a hook and weld it to the second to the last link, there you go, you have a hinge pulling tool.
With the hinge mounted to the car, or firmly in a vice, put the hook of the chain onto the hook of the spring. I usually wrap the chain around my hand so I have real good control but honestly, you don't even need to. You simply pull on the chain and you will easily over come the spring stretching it out and pulling it off the hook on the hinge, then slowly release your pressure on it and take it off the hinge with your other hand, it is that easy. I am not kidding, it takes much less effort to do this than you would have ever imagined.
Putting it back on, do just the opposite, hold the chain with the hook hanging about a foot down. Hook the spring onto the the end of the chain and pull the chain tight while you put the other end of the spring on the hinge, pull the chain stretching the spring until you can hook it over the hook on the hinge, there you go, it's on!
Of course, you need a hood prop or a buddy holding the hood up or when the spring is removed it will fall on your head!
Think of CONTROL the next time you are removing a trunk spring, or any other spring and you will find that this thought about CONTROL will it off or on with a lot less loose teeth and busted knuckles.
Here is a close up of the hook on the spring.