skidsrus

I am having a issue with my rb20det gearbox that i have just purchased, it came with the yoke stuck in the gearbox itself. It still rotates freely in the gearbox but will not come out. i Have tryed whacking it with a hammer even to the point of attaching rope to another to car to help pull yoke free but was unsucessful. Has anyone else had this problem or any advice would be great. cheers