Sorry Dave, I misinterpreted your original post. I would think a vacuum secondary 4 barrel like your holley could be rejetted on the primaries to run well.
Even though you don't have a big block, by the way you describe it running rich, it's probably using fuel like one.
I had a quick look on holley.com and this is the carb they recommend for a stock 289 with manual choke.
http://www.holley.com/0-81570It's a 570 cfm vac sec 4 barrel that they say is "street ready, out of the box."
Phone 02 9829 5072
Phone 0438 658 458
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