I used +10 on my 16's. Worked nicely! So +8 should work (maybe go 10 just to be safe??). I too think the 14" W1 look similar in height to the CS's.
Call the guys at Dr. V-twin! They are a sponsor and will give you a great deal on either bar. You could also check out the Magnum black pearl lines. I think you will regret not getting something braided when putting new lines on. Just my opinion.
Also, if you like the Carlini, disregard Xguys post. You don't need new risers with FLHT. Also, their "electrafied" bagger bars are $325 and come in 12" and 15" heights. That link on page 2 is not the bars you would need.