Tubeless rim tape confusion

[dhelm72]

I went to the LBS today and bought some Stan's sealant, tubeless valve stems and Stan's yellow rim tape.
I have Sunringle black flag expert + rims that are 24mm wide. The mechanic at the LBS sold me 25mm tape but Stan's website says I need 21mm tape for my wheels. How much does the tape width matter?
For what its worth, The mechanic and Stan's website both agree that I don't need a rubber rim strip for my wheels. Am I supposed to pull off the factory rim strip before I apply the Stan's yellow tape or just tape over the factory strip?

Thanks for the help.

[James.Hamilton]

Width wise I really can't help much but it seems you could go either way and be ok.

Definitely remove the existing rim tape and clean the rims prior to stans rim tape install, this is a must. Do a google search for stans rim tape install and follow his methods. I agree that the rubber rim strip is not needed most of the time and I have yet to use one on a conversion.

[TiGeo]

Remove the existing tape.