Great looking old car! A very worthy project.
"examine the metal seam holding up the gas tank"
Very good advice! Here in the salt belt, a friend at college many years ago had a '69 Mustang convertible which was only 5 years old. Filled it up with gas & hit the highway. Hit a bump as he got up to speed & watched with horror in the rear-view mirror as his gas tank, which had fallen out from under the back of the car, skidded down the road after him!
Les