Did you source a T piece ? I'm breaking a set of carbs so I have one available
Stupid though maybe, but, what is the outside diameter of the T pipe could you use a T piece from a aquarium the sort of fitting that goes into a fish tank air line.
As I say it is just a thought, one like that if it fitted is likely to cost you 90 pence and available at most garden centres.
I will measure a fitting on one of my tanks ......................................
4.75mm outside diameter and made of plastic, the internal bore is 3mm.
Not sure how it will stand up to petrol? But cheap plastic fuel cans do.
Just a thought