340 six pack / ‘69 Swinger

Those appear to be the mechanical linkage carbs offered through DC and other sources- driver's side fuel inlets and no vacuum pods, unlike OEMs. From what I understand, basically Bowtie Tripower carbs. Your center carb may need the Holley/Mopar linkage adapter depending where the carbs were sourced, especially if you need to connect kickdown linkage for an automatic trans.