KevinK, SEM makes dyes for vinyl and seperately for plastic parts. It is one of the best products I have used. Make sure you get a can of the "Prep," that is appropriate for your type of part (vinyl or plastic). Since you are working on the dash, you will want the vinyl prep. SEM makes a number of reds so check their paint chips. SEM is truly a dye and not a paint. It is very easy to use but make sure to follow the prep directions to the T and wear gloves to keep fingers oils off the part. I have parts I dyed over 10 years ago that have not cracked or faded and held up beautifully. I can't recommend it enough. NPD sells SEM products and I believe Summit does also. It is a possible the local auto parts store stocks some as well. Good luck with your project.
Jeff