What's your clearance from support to pulleys?
It all really depends on what fans you use. For our setups a single 16" will flow much better than dual 11" but there may also be more clearance issues obviously.
With our radiator and the factory shroud and clutch fan, you may be just fine like you said.
Eric... Right now its kind of hard to determine because the 4-core COPO-style radiator is out so I can only show you some pictures and give you approximate measurements from the core support to the cone of the pulleys. And as we know, the core support is slightly curved with a "bow" towards the center. I put a straight edge on the core and measured from the leading edge. When the radiators in place, there's obviously a slight gap at the outer edges.
I haven't finished installing yet, they sent me a chrome alternator, should've been polished aluminum like the compressor. Everything's loose, nothing totally tightened down. There's a cone-shaped billet pulley for the alternator that I'm not installing yet until I straighten out the polished aluminum swap. But other than these dimensions, tell me what else is needed.
Interesting that you say a single fan flows better, have you tested something like the staggered 2-11" Derale fans pictured? Also, what are the specs on your single fan (CFM, diameter, RPM, Current Draw, Speeds)? Also, can you post some pictures of your BBC setup for a 1st Gen Camaro? I can find pix of the radiator, but haven't seen any with your shroud and fan. As Doug pointed out, the Lincoln Mk VIII/Taurus single 16" fan is one adapted by many performance DIY'ers because of that 4000 CFM capacity, but it has at least a 30 Amp draw, and many will rig it with a 50 Amp Fuse and appropriate wiring, relays, etc..
'69 LeMans Blue Coupe, White Interior, 030" over 454, Super T10 4-Speed, Holley 4150, Pertronix Ignition
CompCams XS274S, 781 Oval Port Heads, PYPES Full 3" SS Exhaust, Hooker Comp Headers, Wilwood Calipers/MC
JGC Steering Box, Helix Uppers/Lowers, ProForged BJs, SpeedHut Gauges, MOMO Steering Wheel, Budnik 17" Wheels