Stop in for a cup of coffee

Yes. I remember he was there in the morning.
Just doing a quick look on the 'net, here's one reproduced by HotRod.
Click full size and download - the scanned photo is huge.
Vintage Road Test: 1967 Plymouth Barracuda 383
https://st.hotrod.com/uploads/sites...7-plymouth-barracuda-changing-spark-plugs.jpg

Might be pre-production. The linked article isn't clear about dates or which parts are quoted from the original print article. The comment about the K-H rims is just wrong. The test car might have had Mag-stars (never used in production) or wheel covers, but not the model year 1969 rims that were recalled.
Looking at the old pic of the spark plug change. That wasn't a fresh engine. Battery caps are green and very dirty. Did note the master cylinder. :)