I would go to Harbor Freight and purchase their $12.99
heat gun and carefully remove all the caulking where you wish to apply the Eternabond tape.
Next I would clean the roof where I want to apply the Eternabond tape very carefully following the directions given by Eternabond.
Only then would I apply the tape. I would not apply the tape right over the caulk as this will not allow the edges to attach properly and you could have leaks over time.
Good luck with your project. I did the whole roof penetrations and edges on my trailer and it was still attached firmly 17 years later when I had the whole roof redone and posted about it
here.Barney
2004 Sunnybrook Titan 30FKS TT
Hensley "Arrow" 1400# hitch (Sold)
Not towing now.
Former tow vehicles were 2016 Ram 2500 CTD, 2002 Ford F250, 7.3 PSD, 1997 Ram 2500 5.9 gas engine