They also sale the prime/adhesion promotor by the quart.
I did my interior w/ 3m di-noc and used lots of the primer/ adhesion promotor and still had a few pieces I had the re wrap due to it peeling up around edges due to heat. Temps inside my bsp have gone as high as 167 with windows closed.
If I where to wrap my roof, I'd heavily use a wax remover and make sure it is super clean, then not skimp on the primer around the edges and not cut the vinyl right up to the edge where possible, like on the sides under the rubber trim, I'd leave a Lil extra if possible and the cover w/ the rubber trim pieces.
I only say to leave a Lil extra on the sides to help it stay down in case a corner starts to peel up, you will have that extra Lil bit to help hold down the rest of the vinyl and also have that extra Lil bit to work with if you have to re stretch it. Of corse the front and rear you will want to cut flush and not have that extra over hang.
Only thing that keeps me from doing mine is the fear of the edges peeling up and it looking like sh!t, then having to take it off and have wasted that few hundred bucks.
I'm also not sure how hard that primer is to get off your paint, if you remove the vinyl in the future and or if it messes the paint up. So you may not want to prime the whole roof and just do the edges and be sure the rest of the roof is clean and wax free. Soapy water will also help you position the vinyl.