When the Coupe was delivered to us it was 2013 + 9 months of Morgans PR use. A fair list of fettle opportunities arose in short time.
Drunken fuel level gauge
Terrible filling rate with blow back
After a couple of goes they did manage to change the pipe to the tank, angle of the opening and wiggle. It would appear to be possible.
I think I remember a thread talking about the small holes around the edge of the petrol filler needing to be aligned correctly for the blowback issue. One of the holes had to be at 12.00 o/c top dead centre.
I am not certain what they did to correct the drunken gauge and it is not perfect but it is at least a LOT better. Before it would not go up past 60% and waved around on bends and under braking. After it would go reliably to 95% and down to around 20% before I failed the chicken test. It would not take more than 60% of capacity to refill. I suspect it was a new sender but with my terrible memory it could have been something else. Andy from AR at Morgan sorted it.