Although I cannot locate the photo right now , one the dealers I frequent suggested moving the filler totally from the car , and drilling a couple of addition holes in the body of it.
I did this and my fuelling is much easier now, and the only issue I have is remembering to ease up over the final litre or it all goes over the bodywork and my trousers!
I may be wrong but I think the standard is one small hole, which can easily be overcome, the additional orifi allow the pressure inside the tank to vent and the filling is much quicker as a result.
