Does This Shackle Look Familiar?

This the rear shackle on my ‘55 frame. This doesn’t look like what should be there. Am I right? What should be there?

This is the front of a ‘57 frame. See the tube coming down from the frame? Any ideas on the purpose? Thanks!

 

Neither are original. Shackle looks like an aftermarket lift shackle. That tube welded on your frame...I have no idea what bubba was thinking there. Cut it off!

 

Figured. Would the rear have been a C shackle in ‘55?

 

Yes.
All CJ's run identical shackles on all four corners from the factory (there are three versions depending on the year).
My guess is the rear springs were sagging so he artificially raised the rear using longer aftermarket shackles and the later elastomer/poly bushings.
You can run either the original C shackle or the later stock four piece shackle/bushing on any of the corners. This is the conversion the PO did in the back, using an aftermarket "lift" shackle.
Many years ago I briefly switched to C shackles on the advice of an old Jeeper. I found a noticeable difference in the ride over the stock bushings and even poly's. I wound up reverting back to the later setup.