On my 62 Starfire upper control arm bushing shaft , the bolts and nuts that hold the shaft to the frame and where the shims are installed. When all assembled the upper control arm covers the nuts for the shaft bolts.
I can get a socket on the front nut, but the back nut is blocked by the control arm. How do you hold the back nut.
The parts manual doesn't show any type of locking device.

 

Those bolts should be captive.

 

I don't think that the bolts are captive, but the nuts and the nuts are hidden by the control arm. You have to loosen the bolts to add/remove shims.

 

Dennis, sorry to take so long getting back here. I originally assumed that the bolts would be splined as on later vehicles, thus my thought that they should be captive. Looking at the parts illustration, it appears that the bolts insert from the engine side of the upper control arm shaft and thread into the frame, no nuts shown in the illustration nor in the parts book. Hope this helps you. If you still have a problem, I would recommend you PM Charlie Jones, he is a wealth of knowledge on your vintage vehicle.

 

 

The bolts do go in with the head towards the engine as per the parts book. If you follow the line down from the end of the bolts there is a very faint picture of the frame and I think a nut.
Non the less, there is a nut there, a 7/8 metal locking nut.
The m/m does mention some sort of lo king tab.
I faced a wrench out of an old 3/8 drive 7/8 socket and the bolts/nuts are tight now.
Thanks everyone for the help.