While fitting a new hammer to my Model 17-3 I discovered an easy way to compress the rebound slide spring when installing the rebound slide. I had a Philips head screw driver, whatever size will just barely fit into the hole where the rebound spring goes. Compress the spring with the screw driver while keeping one of the flutes in the screw driver head aligned with the pin in the frame. The flute allows the pin to capture the spring, barely. Keep pressing down on the rebound slide as you carefully withdraw the screw driver. The slide will sink down over the pin and the spring will be fully captured.
After I did it a couple times it was surprisingly easy. Didn't lose the spring even once.
After I did it a couple times it was surprisingly easy. Didn't lose the spring even once.