hi there i might be wrong but i'm sure we came across this on my bosses old disco.. if i remember rightly they are torx but they're the anti tamper ones so the have a little pin that sticks up in the centre of them all you need is a torx bit with a hole in the centre most diy shops sell them. you may be able to have a close look at the screws with a torch and mirror you should see the pin in the middle of the head...