I have now found the majority of controls on dc6 work with controller despite what i said earlier. The key fact is that most of them, unlike pretty much every other aircraft use a system where you press A to grab the control and then use the left and right triggers to change it.
There’s still the tablet though. You can set the fuel to half or full and you can click to empty a tank and you can click elsewhere to take fuel off bit by bit but you can’t click to add fuel bit by bit. The click spots on the teller are totally off too.