Hi Tash
We had the same problem and used some suction pads found on ebay (see this link - http://cgi.ebay.co.uk/NEW-50-X-20mm-Suction-Cup-Cups-Pads-Sucker-Suckers_W0QQitemZ220268307525QQcmdZViewItem?hash=item220268307525&_trkparms=72%3A984%7C39%3A1%7C66%3A2%7C65%3A12&_trksid=p3286.c0.m14.l1318). They work a treat, dont involve any drilling or cuts to the skirt.