I have a 67 with a 69 bench seat installed. As mentioned above, the 67-72 bench seats should bolt right in.
Here is a link to a thread that talks about 67-72 bracket differences:
http://67-72chevytrucks.com/vboard/s...d.php?t=510997
The metal tag on my standard model seat says 6-2-69. Here are a couple of pics: