Okay, lets get the cob webs out of my head here and see what I can do.
1966 289 Two barrel, "C" code I presume (Code for factory 289 two barrel) put out 200 HP at 4400 RPM 282 ft-lbs of torque at 2400 RPM.
You might run into some clearence probs if your using the Performer RPM Manifold with the origianl carb along with the Carb spacer that has the PCV nozzle on it. I had that problem.
Does your car have single exhaust or dual? You might want to think about converting over to duals.
Oh, I'm not sure of the redline, but I wouldnt really want to tach up a stock 289 much past 5 grand. Although, in stock form, they stop building power way before then. Mine on the other hand

has seen duty up to 6 grand on a few occasions.
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64 1/2 "D" code Red Mustang Coupe. 289, C4, Mallory duel point. Ported & Polished 65 heads shaved .01 with 351 valves, 11:1 comp, 1.7:1 rockers, blue wolverine lumpy cam, modified 4100 Hipo 4 barrel. GT Apperance pkg. And to many others to list
2000 Perf Red Mustang GT. 5spd. BBK Underdrive pulleys, Flotech off-road H pipe. Hurst T-Handle, 40 series Flowmasters, Steeda Tri-Ax
64 1/2 red 6cyl coupe. <IMG SRC="http://cwm.ragesofsanity.com/contrib/blackeye/double0smile.gif">
[This message has been edited by Mercury (edited 07-10-2001).]