Went ahead and replaced my bolts and equalizer this weekend. If you are considering this on a dual axle trailer let me share you my tips.
You need a large C Clamp. Found getting the bolts that go onto the frame to be difficult because the hangars would bow out when the factory bolt was removed. C Clamped them back to straight up and down helped, still a bit difficult though. And it may not be an issue on an older trailer. Use a clamp to help seat the bolts.
Also the C clamp helped on getting the shackles in place between the equalizer and leaf spring. By squeezing them into place.
Using an impact wrench on these bolts and nuts is not a good idea. Ended up stripping out one of the nuts trying to suck in one of the bolts. We decided to just use a socket.
We did install one of the shackles upside down, Leaf spring below the equalizer. Course this was our last wheel and did not pay attention. I was able to flip the shackle by taking the tire off and lowering the axle.
Having 4 jacks really helps. 2 floor jacks seems to be needed.