64 Barracuda Bumper Bolt Size?

I'm putting a front bumper on my 64 Barracuda that never had one when I bought it. Can you tell me what the thread size is for the stainless capped bumper bolts? I looked them up online and they range from 3/8" to 1/2" threads. I do know they are 1" to 1-1/4" long.

Also the bumper brackets to body bolts are a 1/2"-13 x 2" long correct?

Thanks in advance!