I have the Motive Industries system on my 'LATE '65 GT, as it was recommended for the best quality and fit, but acording to my restorer IT had to be tweeked some during the installation, it seems to fit nicely and look very correct for a reproduction system, I would think they would have a system for your '67 as well.
I got mine through Laurel Mountain Mustang on Ebay as they had the best price at the time...