Geoff, I and advice about transforming teak to look like antique pine. If the piece is made of solid teak, not veneer, it is probably more valuable as it is. To try to change the color and wood grain to look like old pine is a specialized operation, and one that would be a challenge even for a professional furniture refinisher. If you are intent on doing this, however, please read up on the techniques for furniture refinishing before you start. Many of the chemicals involved are toxic and need to be handled with all due safety precautions. Coloring wood is a fascinating part of woodworking. It takes time and experience to master. So, if you really want to do this, on that teak sideboard, please take the time to learn and practice before you begin. Unfortunately, we cannot give you a foolproof recipe on how to proceed and to achieve the results you have in mind. We can and do encourage you to take time to learn about the processes of coloring wood and refinishing. There are some useful videos on the processes for wood refinishing and coloration. One source of those is from Jeff Hewitt, owner of Homestead Finishing Products. You may want to have a look at his videos before you begin. Good luck to you.