Vent boots - roofing issue
The rubber on the flashing has deteriorated in just 8 years and is letting rain in around the vents. The old boots are Oatey, aluminum flashing with rubber; all Home Depot carries is Oatey.
Totally replacing the boots means prying up shingles with a flat bar, which tends to damage them even if I'm careful. Then the old boot was sealed on with both a clear calk and a tarry one even though it's marked "no calk." Getting through that really damages the shingles, so the shingles need to be replaced. And messes up the tarpaper stuck to the calk. Did it that way on one boot, it was a PITA. Took a long time, scraped my hands up, got fiberglass splinters in them. Cant't feel the nails with gloves.
What I want to do with the others is cut out a circle from the new boot, containing the rubber seal and a ring of flashing, and then calk the ring to the old boot with a small weep hole at the bottom. The old flashing is perfect, no leak, it's only the rubber that's gone bad. This should seal around the vent pipe, which is where the water is getting in. Any problem with that that you can see?
I also would like to protect the new boots from the sunlight which breaks down the rubber. Would wrapping them with foil be okay?