classic motorcycle forum

Weather is shifting back and time to ride is approaching. I have a 1984 FJ 600 that I have busted the mounting journals. These are 4 collars that bridge over the camshafts. They are made of aluminum and I must have over tightened them. All four essentially blew out. I could easily unscrew 2 of them, but the other two are held firmly in place in another manner. The manuals don't mention them, the part numbers don't exist( dealer specs only show it as a whole top end replacement part) And I have someone who can fix them if I can get them off. Anyone know what the trick is for removing these cam shaft journals? thank you