A lot of that gubbins is already in the box, so the actual unit already has much of the hard work done, can’t be that hard.
Saying all this, we’ll probably not have any more freezing weather and I’ll forget about the whole thing.
Diesel air heater worked a treat today. Put it on at 7am, whole system was defrosted in an hour and ready to work. Got a full day in. Great thing is because it’s linked up to my leisure battery, I can fire it up at work if needed.