I did not know about that '68 error. I guess I have to get out my card and take a look. I got it out of a shoebox collection I bought a few years ago. Has some technical flaws but I am content with it since it only cost me a buck raw:
My favorites are the 1969 regular and AS issue. Again, the regular card was from that collection I bought. The AS card I've had for decades. Both were slabbed recently: