Previous owner appears to have applied silicone caulk over seams. From reading on this board it seems that I need to remove as much of that as possible before application of the coating. It's unlikely to come off all that well. How much silicone is too much? Is it also acceptable to apply the primer over the silicone? If I must remove the silicone caulk and apply butyl or acrylic do I also need to apply the primer over that? Thanks in advance.