Leaf spring strengthening

I've got a 6" leaf set (Full Traction) on the back of my XJ that is too soft. Mainly because of the roughly 220lbs of bumper/tire carrier/35" tire hanging on the back. Once I add camping gear, spare parts, etc, and a body or two I end up with about 1 1/2" of up travel in the rear(not ideal!). My question is - would a 2 or 3 inch full length add-a-leaf work to beef up a 6" pack? My other, much more expensive, option is to have Alcan custom build me a set that would be perfect for what I need, or BOR HD springs (Alcan being the cheaper of those two). Anyway, thanks for any constuctive thoughts/ideas on the matter.

An add a leaf will boost the height and the capacity of any spring pack. If you get too much improvement use the AAL as a substitute for one of the original leaves. Your actual lift height results may vary.

Yea, pop in any full length leaf to strengthen a pack. I'm going to be doing that soon, popping in a full length 2" AAL I have lying around to my 3" HD packs. I want more lift and they are soft, I figure the AAL will help both!