Hmmm I'd say a little risky I have two uncles that are big into cars of this era and well unless you have a ultra trim car I mean have the original sales receipt matching vins perfect everything older muscle can go for a lot but generally speaking the big money market for them dropped out a few years back doesnt mean you cant get money from one or that it wont go up again someday but for the time being they are not the popular thing for the boys with big money.It depends on what kind of profit you are thinking of here a few thousand or 40 50 60 grand the later is going to harder to get in return these days and would always require an entire shop of pros to get a car looking that trim.
So I'd say if you are buying one for your self but dont need to guarantee a big return if/when you sell it go for which one you like.Good MOPAR rides always seem to be less common to me.You need to find someone that you trust tat knows alot about the market for these and how to get your best return would be my advice.That being said I never like to see an add list run times that the owner ran the car in always makes me nervous sucker might have dogged the **** out it.
Myself I have messed around with older Z cars since in the early 90's in high school but I buy them mainly to mess around with and never was seeking a huge profit when I sold one honestly and old Zs are pretty cheap if you know where to find them.I have no personal experience with selling 60/70 muscle cars.All I can say is be careful dont what your mechanical skill level is because there are a lot of guys out there that can make a bad car look good.Dont know about you but when I look at a rid I am thinking of buying a car I bring a pair of coveralls and a flash light with me if you know what I mean.
Last but not least if for yourself (and not your wife or GF) get the ride that
you like. In my case my wife happens to like Z cars as well.
P.S. I know of several great Z car forums so there must be ones for classic Chevy, Ford,and Mopar as well.