Fastener question...where do these go?

[R68GTO]

Body shop gave me a box of fasteners in ziplock bags. Some of the bags either didn't seal or they threw loose fasteners in the box with the bags. Either way, I'm trying to figure ou where some of these belong, hopefully you guys will recognize these....
The first one looks to have been zinc originally and has fine threads around 3/8" die.?
The 2nd pair also appear to be zinc with a funny-looking he'd driver opening and a contained star washer.