I had everything go wrong on my Espar/Mopar kit install. The exhaust pipe didn't fit correctly, the engine mounted formed tubing didn't fit and I had to re shape it quite a bit and most of the hardware was incorrect for my truck even though the kit was the correct part number.
With that said, I love this heater!!! At zero F my cab is warm and the temp guage is registering temp in well under an hour. I am going to install a trickle charger soon though because I can see my wife running the batteries low while she is at work all day. I highly recommend the Espar unit.