Sometimes you get lucky and you can use a bolt & nut, the new bushing and a heavy duty washer of the right size diameter to pull the new one in as the old one comes out. Use a socket (size large enough to catch the spring but also large enough for the old bushing to fit in the center of) or a 3/4 threaded pipe connector so the old bushing will have somewhere to go. Get a bolt as large as you can get. Sometimes you can find a bolt whose head is the right size to pull the new bushing in. Please don't try to use a 1/4" or 5/16" bolt. You'll probably need to exert a LOT of pressure if your springs and bushings are original. If this doesn't work, your bushings are stuck and you'll need to use a hydraulic press, maybe a little heat, a lot of prayer, etc. Grease the new bushing to help it go in. Good luck!
Having said all this, please check your threaded bushings before you do anything else. My experience is that these wear much less than the spring eye bolts at the other end of your spring. In fact, I just replaced all 4 springs on my 1952 and none of the shackle bushings needed to be replaced.
Jon
