BB Curved Neck Radiators.

[Z11Weaver]

I have always thought that the Drivers side tank on a curved neck radiator should have the IO and not IL embossed on the tank according to CRG http://www.camaros.org/coolingsystems.shtml .
I have recently had people emailing me that they have a real curve neck with the IL and OO tanks. The one I’m specifically interested in is dated B. I also spoke with Dave from Heartbeat and he to confirmed that he had seen them both ways and not all that uncommon. Is this true??? Did Harrison make them both ways by means of what ever they had at the time is what they used type thing?

Thanks,

Tom