At the fuel pump.
The nozzle comes on the end of a long tube; this will, incredibly, reach to your fuel tank even if it is on the opposite side of the car! Try it.
(kitescreech still here, Thu 28 Oct 2010, 18:57, 3 replies, latest was 15 years ago)

I do this
Not many people have a 9ft wide car.
( sandettie light vessel automatic New Twitter - @bollocksreally, Thu 28 Oct 2010, 23:52, Reply)

Not always
After reading a tip like this before I tried it to find it doesn't always work.

I have noticed that petrol stations where this is true have signs up saying so.
( Mrs Entity is in hiding., Fri 29 Oct 2010, 20:56, Reply)

Unfortunately....
... this requires that you pull up within about 2 feet of the pump and with the filler-cap no more than about 4 feet forward or backward of the closest point.

This extraordinary degree of precision is beyond most drivers.
( Ugi , it's a game of give and cake, Tue 9 Nov 2010, 13:32, Reply)