I have removed the ejector on two Stevens 200's and my Remington 700; all converted to single shots with a "tray". The cartridge will stay in the bolt head when you draw the bolt back. You will have to pick it out with a finger tip, by running the bolt all the way back and reaching in with your index finger at the neck mouth and gently pulling it out. The two Stevens work great, the Remington is a little more tricky. You have to get a good grip on the case and pull at it at the correct angle. The Stevens are not that picky. Use a 1/16 th inch drift pin to punch out the retaining pin on the Savage. As has been said, there is a plunger and spring. When you punch out the retaining pin, the punch will take the retaining pins place, keeping the plunger in place. When you withdraw the drift pin, put your hand over the bolt face to catch the plunger and spring.
I have never messed with the firing spring, so I can not give any advice here. I would think you could remove some of the spring and making opening the bolt easier however. Before I began, I would get a spare spring, Justin Case and would only remove 1 coil at a time, put it back together and try it with the primers you are going to be using. Some have thicker cups than others. Federal match primers are popular among the bench rest crowd and they have thin (soft) cups. Lightening the firing pin spring is a benchrest shooters trick so the gun does not move at all in the bags when lifting the bolt handle. Personally I have found that the bolt lift is not all that bad, and it gets better after you shoot it a bunch, to smooth it up some.
Good Luck and Good Shooting