If you don't have a service manual yet, get one.
There was a Barracuda Supplement, very hard to find a real copy.
The 1967 'supplement' on this page should be it.
MyMopar - Mopar Forums & Information - Service Manuals
Another resource is the TSBs at
www.hamtramck-historical.com/1967-Dodge-TSB-Index.shtml
Chapter/Section 25 has a TSB on vehicle identification.
