Corsa-B.uk - Vauxhall, Opel and Holden Corsa B Owners Club

I'm in the middle of changing my outer CV joints. I have the car up on stands but cant get the ball joint off, I've tried to take the ball joint of the wheel part but I cant get it to come out, do I need a special tool to open up the gap? I've tried taking the 2 bolts between the ball joint bracket and the wishbone off but they seem rusted badly and I cant get them to budge. Any ideas anyone? Ive been trying to get these bolts out all day and have got no where.

Steve