Grollie bars, was that the contraption we used on the VC10 wing tank panels,
when you got a screw out you screwed the vertical bar in its place, on that there was a split hinged horizontal bar of some length, it contained a floating extension on which you would put a screwdriver socket, on the top you would put an extension and a ratchet handle / breaker bar If I remember correctly. One man would put his weight / strength into forcing the bar down and hence the screwdriver bit into the screw while the other person attempted to undo it.