Strange Radiator Tag

[IZRSSS]

Just curious John (JKZ27); what tipped you off that it might be a Modine? Actually I'm okay with that if it is because evidently they knew what they were doing when it came to high performance radiators. In addition to tractor's, large trucks, etc., they supplied Ford with the cooling system for the 428 Cobra Jet.  Here is what it looks like;
http://www.428cobrajet.org/id-radiator.html

My radiator also appears to be like the one you mentioned; all brass soldered.

[tmodel66]

Marty has Ford parts  Marty has Ford parts   

[IZRSSS]

See...my Ford "Caution Sticker" was right after all.

[JKZ27]

The "^^" is the letter "M" for the old Modine logo.

John