1967 vs 1966 Mustang fastback

You really can't go wrong either way, but my preference would be the 66. It would be a prefect match for your 65 coupe! It is classic to the hilt IMO. I have a 66 coupe and am thinking of getting a 66 FB but have yet to find the right deal. I think there are plenty of repro parts for both 66 and 67. The advantage of the 67 is a little bigger engine bay that allows you to stuff in a bigger power plant without any fitment issues. I like the interior of the 65/66 better too. Just doesn't get any more classic that that!

I would get a 67-72 those both big blocks fit perfectly and the larger trans like a t56.On a 66 you are stuck small block and a t56 won't fit with out cutting on the trans tunnel.But any year mustang 64-73 there a ton of things you can do to them so pick a body style you love and find a nice rust free or less rust one.

I love having my Coupe 65 and 68 Fastback, I like to refer to the 67-68 year as the "true fastback" cause the well, slant of the winow and back was flush down to the end of the trunk, and a fastback 65-66 ends early.

And yea, I'd go with the 67, just cause its a slightly improved, different vehicle, unless you want to drive the same car with just a fold down rear seat and a different back window.