![Image](http://www.fordification.com/board/cowl-lacing-holes.jpg)
As you can see, the '67 trucks have round holes instead of slots for the lacing clips. The spacing is close between the two, but there are a few differences here.
The '67 lacing is attached with eleven 1/4" round holes, spaced 4-15/16" apart. The distance between the centers of the two end holes is 49-1/4".
The '68 cab has eleven 1/4" x 1/2" rounded slots, spaced exactly 5" apart. The distance between the centers of the two end slots is 50-1/8".
Now, the interesting part, in case you haven't already noticed in the above picture, is the LOCATION of the cowl lacing. The '67's is mounted down lower, below the firewall ridge, whereas the '68's is above the ridge. Therefore, it would seem to me that the '67 lacing needs to be taller to reach the hood lip. (I compared the back lip of the '67 hood with the back lip of a '71 hood and they're both identical, so the difference has to be in the height of the lacing.) Unfortunately, I don't have any cowl lacing remnants from either truck to compare.
Well, so there you go. However, this investigation isn't over. I don't have any other trucks to check out, and I'd really like to get a definitive comparison between all years...so those of you with '69-'72 trucks can help out here. I need you to take some measurements of the spacing of the slots in your truck and see if there are any differences for those years that I haven't mentioned yet.