Hesitation issues - need help

Id throw all your tinkering out the window, get a rebuild sheet and put everything back to spec including the idle screws (seat then give them 1.5 screws out). pretty much everything under the fuel line depends on the proper float level so thats what needs to get checked first. Time it then set idle, then start turning screws equally to set highest vacuum, then reset idle, back and forth until there is no change. Most Holley carbs come jetted right, out of the box even for slightly lumpy cams. PV should be about 2-3 inches below criusie reading. 6.5 is about stock. The old "PV should equal 1/2 the idle vacuum reading" is somewhat of a ballpark now. If you have a vacuum gauge you can watch in the readings at cruise. You want the PV to be 2 below cruise, anything less and your running rich off the PV unnecessarily.