Thanks for the update and that's one useful tool so thanks for the link.
Re a leak around the fuel pump. Would not this happen ALL the time the car is running (and be quite dangerous)? In my case the fuel smell is ONLY when the tank is quite full and then the smell goes away as fuel level reduces below about 3/4s full.. Makes sense to check it out regardless.
Quite perplexing especially with no codes. It seems that empirically ruling stuff out may get me to an answer...eventually! Sigh.
It's been raining here for a few day so when we eventually get some sunshine and the roads dry out, I will put a few more miles on the vehicle