I did some more searching and I found a flow calculator from martinsliquidlab and this is the revised setup. I am partial to the 1 loop idea now, with the video cards in parallel...
Attached is a drawing of the new loop...
All of the part numbers are Koolance part numbers.
1 X CPU370 - CPU block
2 X VID-NX590 - GTX590 block
1 X INS-FM17N - Coolant flow meter
1 X ERM-3K3UC
2 X VL3N-M13S - QDC (High Flow) No-Spill Shutoff, Male [For ID: 13mm (1/2in), OD: 16mm (5/8in)]
2 X VL3N-F13S - QDC (High Flow) No-Spill Shutoff, Female [For ID: 13mm (1/2in), OD: 16mm (5/8in)]
6 X NZL-V13P - Nozzle Pair, Compression [For ID: 13mm (1/2in), OD: 16mm (5/8in)]
2 X CNT-VDA34 - Dual VID Connector, Adjustable 2-3 Slot Spacing
Might add 2 more quick disconnects for disconnecting the external cooler from the case
Comments? Suggestions? Did i miss anything?