I think you'll find you can no longer pump any type of petrol into overhead tanks with a mobile tanker that uses a hand-held hose inserted into the filler pipe mounted on top of the tank.
The reason being, accidental spillage falls back down onto the tanker and the ground and creates a serious fire hazard.
The only way an overhead tank can be filled is if the tank has proper fill piping installed with a proper camlock coupler and a one-way valve to prevent fuel losses in case of accidental detachment of the tanker supply hose.
The tank also has to have some form of automatic fill cut-off when it reaches maximum holding capacity.
I used to have an overhead petrol tank in the wheatbelt in the 1960's and the local fuel agent used to just use an 8 ton truck with a fuel company bulk tank fitted to it, and pumped out of that tank with a portable fuel pump powered by a single-cylinder Petter diesel.
The tanker supply hose was just inserted in the top of the tank and the refueller had to watch he didn't spill any petrol.
However, the authorities clamped down on this system and outlawed it, when a couple of refuelling tankers caught fire when a refueller spilt petrol from an overhead tank during the fill process, and it splashed down onto the hot exhaust of the pump engine.