If you feed them thigh meat and other muscle meats often, I don't think they need taurine at all. I don't give taurine to my 2 cats.
The more a muscle is used, the more taurine it contains. Thigh, leg, wing, heart, kidney, are all good sources, followed by breast.
I don't worry about percentages. I just got into a routine that I feed them whole Cornish hen every 3rd or 4th day, then pork, chicken, turkey thigh, Salmon, egg, etc. One of them won't eat liver but will eat hen back that contains kidney.