Engine mount confusion

'66-72 B-Body Products

I think the drivers side can be shimmed up with some washers if you wanted to try that instead.
Yep. You just gotta be patient and get the shim thickness spot on, so that when you torque down the bolt in the back, it does not overly stress and snap off the back ear on the block. (The same can happen with a proper mount if one of the mount ears is bent too far off....)