This is a pic of the dashboard when i had 1256,7km done.
I had around 100km left of range.
I did a little tweaking to the batterie bank i had in the trunk.
I taped all the poles of the batteries, except for 1+ and 1-.
Maked an mounting harnes (witch is held in place left and right by the with of the wood, and up+down & front+back by the yellow strap that holds the bank in place.
I added a relay between the black negative wire from the bank to the 1000W inverter (from 12V DC to 230V AC).
Then i put the switch from the inverter on "on".
I plugged in this 1500W heater.
Set it at position "1" (=750W)
Position "2" = 1500W
Position "0" = OFF
The red switch at the shifter controlles the (200A) relay.
And by that it controlles an 750W cabin heater
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Witch is trapped and held in place between the net and the back seats.
No more cold in the car.
Now I only need to install an remote controlled relay in parallel with that red switch and i can remotely start the heater to preheat the car.
The only down side to this, is that in winter, when i use the heater until the engine is at operating temperature, i need to charge every 2 days, instead of every 4 days (yes, i only work 4 days in a row
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).