427 down on power

[Excaliber]

"Reluctant to rev", that description just doesn't sound like a carb issue to me.
Verbal or typed descriptions/symptoms are particularly difficult to get a handle on, by the way...

Of course if the secondaries aren't working that will reduce the horse power, but it should not make it reluctant to rev. THAT description does sound more like:
Plugged exhaust (not likely).
Retarded mechanical camshaft timing.
Retarded ignition timing, base or advance curve incorrect or sticking mechanical advance.
Along with plugged exhaust factor in valves sticking in the guides or grossly misadjusted, which could give the same symptoms as plugged/restricted exhaust.
Weak spark, can't fire the fuel properly.