The AFE inlet would be a complete waste of money. I would expect the stock LBZ mouthpiece to flow better than the AFE.
I personally don't like hot air intakes with sheet metal heat shields that half-ass try to block the filter from sucking hot air from under the hood, then metal pipes that transfer even more heat into the air on it's way to the turbo. Having a 5" intake pipe feeding into a stock or AFE moutpiece is not going to do anything for you.
We have installed a stock LBZ turbo inlet and stock LBZ intake on an LLY and dynoed 590 rwhp on Dunbars dyno (on fuel, stock turbo). We have a stock LBZ mouthpiece and S&B LBZ intake on an LLY that dynoed 604 on Dunbars dyno last year on a stock turbo fuel only, then dynoed 604 again a few weeks ago, then 636 with a drop in BatMoWheel in the stock charger.
On my personal truck I was running an S&B LBZ intake box, including the tube that the MAF is in, when I competed in the Diesel Power Challenge and when I ran 10s @ 136 mph in the 1/4 mile.
On LBZs we have dynoed 540+ with a down-pipe back exhaust, lift pump, shimmed FPRV and tuning - and we aren't the only ones. Based one what we have done on stock and/or stock style intakes I really doubt your intake is what is holding you back right now and wouldn't expect to see any gains at all out of changing it.