The spring should just drop into the trem bar hole. Unscrew the trem bar right out, drop in the spring, screw the bar back in. It will make the bar stay in place where you put it and greatly reduce the 'wiggle'.
A pro set up would be recommended, or you can research and learn. Basic set up is not rocket science as they say, but it's nice to get a good starting point done by a professional. I find the nut slots are a really key factor. Make sure they do what needs to be done. Good luck!
...so ever since then, I always hang on to the buckle.
