The best way, that I have found, to prepare the roof for repair, no matter if its EPDM, TPO, etc., is to wash the area you are going to seal with a small amount of dawn and water. Then wipe dry, apply denatured alcohol, let dry, then apply the sealant/tape.
I redid my roof on my 38 footer and used nothing but Dicor self leveling. Have been through several hard rains and not one leak (knock on wood).
If you are going to use the tape be sure and seal the edges and ends with Dicor.
Retired Army, Disabled Veteran
Wife, me, and 2006 Coachman Cross Country 372DS makes three, Demco Kar Kaddy SS