Will be fitting a central bath mixer on the bath and would like some advice on the fittings to use. I have existing 15mm speedfit that I have currently blanked off. As the taps will be central mounted then it will be difficult to gain access so will need to fit taps prior to fitting to back wall. Do I go for the JG Speedfit flex, but internal bore is 10mm. Will this cause me problems with reducing down??? System is Combi Boiler - Mains water fed. Can anyone give advice on this?