Actually, the BDS leaves were made for the hardbody. They just happen to work on a Frontier.
I have a set and they're a nice upgrade, however, I'm replacing them with custom Alcan spring packs as soon as the new springs arrive because the BDS's don't provide adequate lift out back for my SAS and I'm having to use very long shackles to compensate. With your IFS lift, though, they'd be ideal.
As Snuffaluffugus...er...BigBird says, the sites he listed do offer aftemarket lifts for your truck. Consider also a steering upgrade, as the stock centerlink is typically short lived once you start cranking up the IFS. Hoohaa centerlinks (an ad can be found for him over on my site,
http://www.nissan4wheelers.com), or Calmini both offer solutions for your truck.