On the inside I added bubble foil insulation around the pipe where the hot air comes out of the furnace, and it is amazing that nothing inside the seat gets warm while the furnace is running.  The cold air coming into the seat box keeps everything inside the seat cool!

The tank looks like this when mounted under the RV.  When the tank is in the up position there are two aluminum posts that slide through the frame and clips are pushed into place.....I also added a safety chain in case the pins fail.

The heater worked flawlessly for the 3 nights we used it.  We burned it 6 hours each for the first 2 nights, and 8 hours for the 3rd night.  We used only 2" of fuel from the tank height in that 20 hours of use - so it runs about 10 hours on a gallon of fuel!

The heater has 6 heat settings, and in the 50 degree temperatures it could easily heat the RV on the lower settings of 2 or 3.  The highest heat setting of 6 was used a few times to get the heater started and just before shutting it off - the folks who use these a lot claim that running it at low settings continuously can soot up the combustion chamber......so they recommend running it at high temperature for a while before shutting it off.  When you turn it off the heater goes through a shut down cycle and keeps the fan running until the burner has cooled down.  The heater takes several minutes to turn on and come up to temperature....and several minutes to shut down.  You need to turn the heater off at the controller and allow the system to shut down properly - if the power is cut off and the heater is not allowed to go through the cool down cycle the heater will be damaged.

It took me about 4 days of work to get this thing mounted - but it is a huge improvement in our efficiency and ability to camp without access to utilities.  It heats our 30' long RV well - the 8K capacity is likely a bit too much for a small camping trailer or van.......maybe the 5K would be better sized (or for a really small camper maybe the 2K version).

Another option is the portable unit - it takes far less work as you only need to figure out a way to provide power and a place to run the hose into the camper.  It may not be as efficient as you will lose some heat in the hose - but that may be a benefit...in a small camper you may even need to vent some of the hot air out so you don't overheat inside!
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