Not much work with Christmas and New Years and starting a new job, however I did spend a lot of time researching panel marking methods. I never thought there could be so many ways to do this.
I settled on using a Brother P-Touch label maker and their heavy duty plastic tapes. It took some time calculating all of the dimensions of the spacing but I finally got it to where I wanted it. These are white ink on black tape. I have saved the files so if the heat or sun get the best of them I can always make more without going through all of the setups.