Marsh_Man

I have a 91 that came to me with solid 6" blocks in the rear. I want springs. I am pretty much budgeted for the ProComp 23411's which I have read is 6". But does this include some kind of factory block? I am not even sure there is one, I just came across that in Bronco forums. If so, should I be adding some 2.3 degree 2" blocks as well to achieve a full 6"? Lastly, new shackle kits, good idea or is that not necessary?

Thanks

Picture attached of what's currently under there