Courtenay got back to me today with the mod that is required to fit an uprated fuel up into the ZLet fuel tank.

I am sure Courtenay use Walbro pump which are cheaper than the standard replacement beleave it or not lol

here are the pics and quick descripction of what to do.





Basically it is remove the lugs where the arrows are pointing towards the outside of each image and on the second image the outer ring where the arrows are pointing towards the inside needs to be reduced in height about 5-7mm certainly no more than 10mm but its easier to remove than add it back in!, to fit the pump securely.
Now I just need some extra pennys