The F is likely a maker's mark, so don't worry. The short keepers go on each end. On a 216 there are studs, without threads on each end, to assist in alignment of the manifold (along with alignment rings for the intake). The manifold assembly is held with bolts (no nuts) so you could use anti-seize on the threads to assist in removal in the future. I believe Ed's picture is for a GMC engine.
Kent
Last edited by Lightholder's Dad; 02/22/2021 12:54 AM.
