I'm trying to remove a distributor from a AQ131A and after removing the clamp bolt, distributor will not pull out. Engine is 30 years old. I have wedged it up by hammering in a thin chisel. I am at the point where it feels like I might break the housing. I have done lots of engines but mostly diesel and USA engines. Is there some additional pin, screw, etc. that has to be removed to release the distributor?