I found a easy way to install the hammer spring retainer clip. I used a 1/4" nut driver with a hollow shaft, put tape over the end so as not to mar the clip and for friction and just pushed the clip into position. Amazing how easy it was.
Another good idea............I've used a screwdriver (or whatever plastic-handled doodad was handy) and once it's lined up, I just press down on the clip, and ride it down until it snaps into place. I'll give your trick a try.