A few years ago (10?) I tried dying white mohair a taupy brown. I bought a perfect, steiff bear head at a flea market for $20.00. The poor fella lost his body and all 4 limbs in a flood. I had a piece of white mohair that the quality matched quite well, so I made him a body (it couldn't do any more harm than he had already suffered). I do have a bit of dyeing experience, but I couldn't tell you exactly what I did for that recipe. I played around with tea and coffee combinations, until I matched the colour perfectly. He was displayed in my daughter's room, not in direct sun light, but not protected in a special way. Unfortunately the dye has faded considerably, turning a much lighter, reddish brown. I have an wonderful bear by a well known artist, that has a clown collar that is fadding considerably too. I've often wondered if anyone has kept their dyed creations around for lengthy periods to see how the dyes are holding out. If records were kept, it would make for very interesting info.
HI! I don't have a whole bunch of experience in dying, but the research I have recently been collecting indicates, Tea will vary by color per it's recipe, eg. orange pekoe will come out more peachy than say english breakfast. Also there is a certain amount of vinegar to be used ( i don't have the recipe) to keep color.
The techniques I have seen used most often require teddy's pieces to be cut out THEN dyed, airdried, fluffed and sewn together.
GOOD LUCK! ren