I put the taps on under neath bath but the hot was on cold tap and visa versa. I could.nt put them on any other way as the taps would have been facing outside the bath underneath. I then put yhe shower head onto yhe wall in side the shower running off new taps but it only runs the cold

We need more information. Is your valve one handle or two knobs? What's the brand name? Are you saying the hot and cold are reversed? Let me know, tom