Just posting this link to a good set of pictures of a 70's model GT with the flow through ventilation indicators under the bumper and those god awful tail lights
I don't see many photo's of these around so though it might be of interest. The laptop I'm using here doesn't have the Japanese language pack installed so I can't translate the page but the pictures are worth a thousand words... or something like that!
http://www.n-classiccar-jp.com/car/isuz ... bellet.htm
Enjoy.
Cheers,
R.