DITCH the double block GARBAGE.  Keep the 2.5, but add a Belltech 6400 shackle and a short AAL.  Those two will replace that SL block and give the same ride height.  I saw 1.5" lift from each.  OR....get expo leafs and shackle for a better ride and same ride height.  Don't forget new U-bolts 'cause the SL's are crazy long.  
The Duff baby bars will work fine for what they are....but I find, I still hop pretty crazy.  Gotta love a manual and a locker.  lol.   Don't get me wrong, the Duff Bars everyone gets are great units and do a decent job, but with the weaker spring rate Expos for softer ride, the leaves don't help with the pinion pivoting .  Ever since the Expo install, I've removed the bars 'cause I ran out of U-bolt threads.  I've got the Duff long arm bars from a BII I hope to adapt to my Ranger, but will likely never get around to it.  I'll probably fab a bar with a shackle and heim instead.