A group of photos from the 12 Hour Race at Sebring in 1964.
One photo includes a Corvette Grand Sport - one of the 3 Coupes built - all three raced that year ;

These are from Karsten Stelk archives.

The #33 photos
Name:  AH 3000 #360 Sebring 1964 Cars #33 and #34 . car #33 K Stelk archives .jpg
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Name:  AH 3000 #361 Sebring 1964 Cars #33 and #34 . car #33 rear K Stelk archives .jpg
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Name:  AH 3000 #362 Sebring 1964 Cars #33 and #34 . car #33 Corvette and Cobra K Stelk archives .jpg
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Oops - that does not look good

Name:  AH 3000 #366 Sebring 1964 Cars #33 and #34 . car #33 shedding tyre K Stelk archives .jpg
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