Would putting a hood tach, be a plus our minus for my standard 69 gto, in regards to
resale? It has a tach in dash already but is pretty puny. Also has spoiler so already not
This was such a common option on these cars no one would probably know it was not stock unless you were entering a competion as a stock 69 GTO. Even then it would be tough for anyone to say it was not original. I would go for it and put it on. I think they really enhance the look of the car.
Given that you have it non-original already, do what you want. I wouldn't suggest it on an otherwise all-original concours car, but if you like the look, go for it.