Already closed but interesting build non-the-less
http://www.ebay.com.au/itm/Fj-Fx-Holden-4x4-penal-Van-/280812404405?pt=AU_Car_Parts_Accessories&hash=item4161b93eb5
There's a wb one getting around my way like this,
I think there were overlander kit made for them as well, but not very popular,
I've driven a hz overlander and there very capabul 4b's as they have a very low centre of gravity and normally fitter the v8's so plenty of power.