I looked in the AIM and found the clips. There are two of them that look like they correspond to the location of the two 1/4" holes in my firewall. I could only find an illustration for the six cylinder so I'm not positive how the V8 is configured. Part #3771077.
The only place I could find them was at Corvette Central (
http://http://www.parts123.com/corve...50b&ukey=34290)They describe it as 1/4" brake line clip which is much larger than the 1/8" oil line.