no not at all really, just get the angle right and lots of blades needed. then just use some acetone once its all removed to clean the area, (even grease from finger prints can effect the bond)
then resilicone,
use duct tape to hold the sides together whilst it sets, another idea is to run a line of masking tape down the side about .5" from the edge, so this can be peeled back whilst the silicnoe is still tacky to give a nice finished edge.
hope this helps.