[G.R.]

From what I could tell your car may be a NAF (North American Fiberglass). I see a lot of similarities between yours and my old 289FIA, ie. frame and MII front suspension, forward leg brace on roll bar (most NAF's built had that type supplied w/chrome an option) street dash option, hood latch, hood and trunk hinges, door panels and the wheels look like the stock wheels supplied by NAF.

If it is a NAF there should be a serial number stamped on the passenger side rear frame rail on the top...it'll begin NAF427 followed by a series of numbers ie, 693(mo/yr built)followed by a production number. Also a build plate was mounted on the firewall on the passenger side near the rear of the front fender...rather hidden and often painted over