Here's more info in an old thread: viewtopic.php?f=5&t=455
Got a roll of UHA tape and put it on the other day. Pretty great stuff:
I learned quickly that it doesn't turn- I started across the front of the PH and at the corner had to cut and start a new line. Cuts with scissors, but you can easily score a complex shape through with a razor.
My roof was "clean" from washing and painting the rust and bare metal, but there is a lot of dust here so I went over the whole area with rubbing alcohol and a clean rag.
Then, I started at my Fantastic fan edge, I'd recommend starting at one side to do the whole PH front- 90º cut where the roof meets the drip rail and you can pull the backing and adhere the tape as you go. It conforms perfectly to the roof ridges.
At the other side cut 90º with scissors at the roof-to-drip edge. Cut before completely removing the backing and you can test fit your cut to the edge.
Then with another 90º end start back and go down the entire side. I put one edge at the drip rail and tried to follow that with the tape, sticking that edge down as far as I could reach on one placement of the ladder, and then once the edge was along the contour of the roof (there are some minor variations), rolled the tape along the roof curve- meaning running fingers down front to back to press the other half of the tape down.
I then followed that side section up with a burnishing roller from my Dynomat project to get any bubbles out of the edges. Meanwhile the tape roll sat a the head of the next section, such that I did three passes for each section before moving on.
The tape itself is fairly forgiving at application- a few times my edge matching pointed me into space as I stuck the tape down, and you can just peel it back up. I'd go back a few inches, readjust and reapply. There didn't seem to be any stick issues the second time as I re-adjusted one section more than once.
At the back, where the roof corners curve I applied the tape and then used a razor to contour to the roof-drip-rail edge, then peeled away the excess tape.
Next, repeat on the opposite side and you are left with another 90º end piece to do the rear. On the rear piece I used the razor to contour out the factory 3rd brake lens, as even though I tried to dip into the drip rail at that point to avoid it, it was on the edge of the lens.
So all in all, very easy with UHA tape. I had a good enough portion of the roll left over too, possibly enough to do one full additional side, had I buggered it that badly.