Interesting, never seen one with the fuel pickup mounted as such.
Things Ihave learned with mine was make sure the air intake is very protected, as I have filled mine with snow. Other thing was as my tires kicked up mud right at my pump, a fitting came loose. Both will be getting improved before the winter for sure.
But welcome to the life of pre heating the van for when it is cold between the fire and your bed! I probably use mine more than i should, if for any other reason that it is good to have hte heater get up to temp once a month.
I put a lawnmower air filter on the combustion intake hose. Something like the filter at the link below. I don't recall the size of the black hose so verify that first. I picked up the one that I used at our local ACE store and it fit perfectly.
There are mufflers available for that exhaust outlet. It will reduce the operating noise substantially. I was looking for a link I could give you to which one I bought on ebay but no luck. Highly recommended.