UPDATE: I've found two small articles that confirm the event as the 6th annual Braille Rally in Jun/Jul 1967 (exact date TBC).
One item is from the Jul 1967 issue of the Cobra Crier (Shelby American staff newsletter) and the other is from the Sep 1967 issue of the SCCA's Sports Car magazine. Am still trying to ID the Cobra, one of two entered in the rally.
---
from SAI's Cobra Crier, Jul 1967:
from SCCA's Sports Car magazine, Sep 1967:
One item is from the Jul 1967 issue of the Cobra Crier (Shelby American staff newsletter) and the other is from the Sep 1967 issue of the SCCA's Sports Car magazine. Am still trying to ID the Cobra, one of two entered in the rally.
---
from SAI's Cobra Crier, Jul 1967:
from SCCA's Sports Car magazine, Sep 1967: