Does anyone know the size and length of the factory bolts that hold the upper control arms to the frame? I have to get some longer ones since the factory are a little short to shim out enough and would like to pick up on way home and change them out. Its a 64 chevelle by the way. I know the knurled ones are better but I have no choice.

I know they're 7/16" dia and I'm guessing the length to be 2 1/2". Use a Grade 8 bolt. :yes:

If they're same as on the 70 go to a Chevy dealer and pick up a new one, they still have them around at some dealers. A regular bolt does not have the knurled shaft to lock it into the frame. I think I paid less than $3 for one a couple years back.