Hello! Looking to attach a curtain track ideally about 15cm above bifold doors - any advice on what sort of fixings to use? The curtains are thermal blackout for the winter and therefore quite heavy so I think it will need at least 4 fixings to span the 2.4m width of the doors. The bifolds were already installed when we moved in, but I imagine there may be a steel above? Will we just need to bite the bullet and start making some holes to see what the options are, or is there a better way? Thanks in advance!