Fuel filter heater, both coolant and electric wrap in case things gel up because you've got the wrong fuel for the climate at the time, it also allows your coolant heater to pre-heat the fuel making for better running.
If it is going to be really cold add silicone heater pads to the oil pans and the fuel tank so you can keep those from getting too cold or warm them up if things fail to start as expected.
I am currently running B100 down to -20C which is why I've been dealing with these issues.