Opinions on this '68 Barracuda

So knowing the VIN now we can determine it was a /6 car (B) so the K-frame change or conversion mounts have been used. if built/ converted for racing I would "assume" K-frame. So with that are they spool mount or pad style?
The disc brakes are they single piston big bolt pattern of 4 piston kelsey-hayes small pattern.
Again though, what the car is worth is what are you willing to part with to own it. check avg prices do a quick check list in your head of things that you want to do to the car that will make it "yours".
Your skill set will also make a big difference in the whole "diminished returns" aspect of the car. The more you're capable of doing the better you are in liquid assets (cash) invested. Myself my time is the love of the hobby and being productive with my time, so I don't count it directly.

Body parts for these cars are not really being re-poped, or are just starting to get some needed attention and tend to be the most costly for good metal. grilles, fenders, trim seem to be upper end cost items, while a lot of other parts are very interchangeable and accessible.

I think for a little bit more you can find something, more correct that will have better future value overall from an investment stand point.