1971 198 slant 6 manifolds

There are 3 bolts that bolt the exhaust manifold to the intake manifold . 1) can’t find what size these are 2) do I need them ? Do they get any sort of gasket between them ? I don’t see why they would I’m trying to put my head back on this weekend a d those are only 3 bolts I don’t have .
Not looking for the studs that hold manifolds to head ; looking for the 3 bolts that hold manifolds together around where carb mounts