When I did mine, I undid the bolts that held the carrier to the frame. I then unthreaded the bushing. Measurements are REAL handy here. Whatever you do, do not measure just the rod end of the bushing, as the parts might be slightly different. Measure from the carrier to the lower control arm.
Once I got the bushing swapped, I threaded the bushing all the way in as far as it would go and then used brute force foot/body/tounge manuvering to force the carrier into position enough to put a bolt back in. Once the carrier was back in, I threaded the bushing rod back to the approximate measurement.
I think I shocked myself at all the colorful words I came up with during this procedure. If you can figure out a way to keep that lower control arm from coming back at you when you remove the carrier, your life will be MUCH easier. Last but not least, get a proper alignment at a shop that knows how to set up a 126.