My 1997 STS needed a head bolt repair - bolts have pulled out. My problem is that I can't figure out how to remove the head centering studs in order to install the templet for installing the time serts. I have done all the bolts on one side but can't get these two centering studs out to allow the drilling and threading of the first and last cylinder on each side of the engine. The only way I can see to do this is to remove these studs.
I need help on this one

Thanks Doug