Al,
Herb McCandless told me this trick. Put the short end of the spring in a vise. Bend it to one side then stick a bunch of washers in the open coils. Bend it the other way and stick washers in the other side. Now install the spring then start pulling out the washers with vise-grips. Here is a pic of the switch. I'm glad that you are putting one in , if you didn't have one before. I had to fix my front fender because some d!ldo decided to bypass his switch, then trade his car in. I went to start the car and I crashed it into my own Challenger!
Good Luck,
R0B