personel choice   I went witha e-bay Aluminum 209.00orks well  Some like it  some don't 

http://cgi.ebay.com/ebaymotors/1966-1967-CHEVELLE-REPRODUCTION-ALUMINUM-RADIATOR_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem35a2f9b618QQitemZ230367540760QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

(CLUTCH) thats better.

If you have changed your alternator and PS setup, ie: gone to the long water pump instead of the origional short one, you , like me, will probably have issues with a 4 core BB rad! There is not much room, however a small spacer on the front of the waterpump, and a small flex fan with shroud, it will work!! (its been a fun experience figuring all this out!!) As far as aluminum goes, you can paint it black to look origional if needed. Another trick I learned, if your hot rod never sees winter (heated storage) all you need is @ 10% antifreeze and the rest DI water and a bottle of Water Wetter. This will drop your running temp by @ 10-15 deg! Seems thet water gets better contact with steel than antifreeze, and allows for better heat disperal from the block! Who would have known!

I assume that the aluminum is stamped to look like original (mine is)



and aluminum is clearly more efficient and less expensive, and if you really want it to look 'original' you can spray it black, so I would recommend aluminum.

Dave