Holley Carb Troubleshooting

I have a Holley #6710,4165 spreadbore carb it has mechanical secondaries and center feed bowls. I recently tore it down the jet's in the rear were 15 sizes above what they were supposed to be.They are now 2 sizes smaller than original . I was told these carbs run a couple sizes rich anyway . 61 front and84 rear.I cleaned the air bleeds,cleaned the whole carb.checked the power valves.it has 6.5 on both sides the book said it should have a3.5 in the rear would this make a huge difference?I have it back on now , it run's a lot better but the secondary linkage seems to bind up occasionally.Do I need heavier return springs? or should I run a seperate spring for the secondaries?I would appreciate any help.