I have an 09' TRD off road Double Cab with 50,000 miles on it. The previous owner did not have the TSB done so it has the original 3 leaf pack. I was looking at the packs today and it appears as if they have a negative arch. I am going to attempt to see if they will do the TSB out of warranty (I know my chances are slim and none) but when they most likely say no, what would my best option be? AAL or replace the entire pack? I have a topper on the bed and the truck sits pretty level and is even slightly nose high. I was thinking about doing 5100's all the way around with either the AAL or new leaf pack. I don't need the truck to sit level and wouldnt mind the stock look of it being slightly bed high. Thoughts??