Ok, so the guy who was helping me install the shackels decided to put the jack and towers on the differential instead of the frame, and then he unhooked the stock shackle from the bottom(since u cant do it from the top because of the metal sheet), but now the leafspring lowerd and the shackle is pressed up against the bed underneath.Now we have to put the towers on the frame(as i told him b4 we began). So pretty much what i am asking is, did u guys have to take off the leaf spring to install the shackles on the NNBS and what are the best ways to go about finish this job in which i just described to all of you.

 

support the frame of the truck
put jack under differential, lift rear slightly remove bolts from one shackle, use jack to line up holes put the bolts back in.
repeat for other side