I have a Holley 6oo and would like to know since they have a plate for the secondaries, how do you jet the secondaries. It is a common thing to do on ones with screw in jets. Do they have a bunch of plates available.
The kit linked above is only for center-hung float carbs. If yours is side-hung, Holley has a kit to convert to jets for those. Cost by the time you buy the kit and jets is similar to buying multiple plates - but easier to re-jet, and can be staggered jetting in the unlikely chance your engine needs that. What carb model do you have?
That would be a Holley 34-6 kit. I think I have one hanging around here I could make a good deal on. However, I just found superflowcarbs has custom drilled (jetted) plates for under $5 and cheap shipping on eBay. If you're close and only need a couple to nail it, that would certainly be cheap. Still a bit more PITA, but you're not re-jetting like a racer.