What part of the Holley is hitting? The throttle linkage? Some Holleys need a spacer in between the carb and the filter base plate. If so there different types of filter base plates to address the issue. Some of the base plates have a drop that allows hood clearance, some are flat with no need for hood clearance, some have "notches" for the throttle linkage to clear and they have to be lined of correctly over the throttle linkage.