68 Barracuda mystery - Can someone provide some information?

Definitely a 70s custom.
Head over to Instagram and look for old school street machine accounts, might find a pic of it in it's heyday.

Or check here:

Street Freaks, Customs, Rods, Street Machines...60's 70's 80's
The valve covers are from a 70's car. Not sure why that would be, unless it may be a 70's motor.