Correct door window guides for a '68?
 

I'm in the process of disassembling the car now for paint. I noticed when playing with the window adjustment, that the slotted hole for the door glass guides was missing a guide.

I see several styles on ebay for sale - but I'm wondering what is correct? Anyone have a picture or a link to the correct window guides for a '68 GTO? It appears there is only one at the back part of the door.

Thanks!