SOLVED!
It transpired that the fuel smell was due to one of the new ignition coils boot, not being located over the spark plug hole correctly.
luckily I have a good sense of smell and managed to locate the smell to the spark plug area. I found no other leaks anywhere. I had recently changed the plugs and coils. On further inspection after following my nose, I could see that one of the boots wasn’t entirely over the spark plug hole, this is where the smell came from. I checked tightness of the spark plug and then repositioned the boot correctly. The smell hasn’t returned since.