COngratulations. Very nice truck. I wish those were available here.
The cage looks very sturdy - are you planning on rolling it?
The wheels you have on fit the truck very well. The new wheels you have ordered will give you a few new "abilities", imho: Bad looks, more wear, higher fuel consumption, less flexing (important offroad), less friction/grip and worse handling. The only good environment for fatter and lower profile, is dry, paved roads if you need high speed. If you need bigger tyres, there is the 255/85R16, which would suit this car very well, if there is room for them.