I can't speak to your particular application but I can report that on my stock 440 I'm running an AVS Thunder 1813, which is 800 cfm, as recommended by my restorer at the time. It works "fine" without any particular tuning. I do suspect it's a bit "much" for the car, academically if I were...
Reminds me of the clowns piling out of the Mini... they just keep coming! I'm more a slabside guy but I have to give props to the fusie crowd. Haven't seen that many together even in the 70's....
Notwithstanding the quality issue, a lot of the parts which are easily available locally may be because they were used on Dodge vans up into the mid 1980's....
If you decide you need a '66 column, I have at least one (not T&T though) which is yours for the cost of shipping. Shoot me a private message if you want.