I guess this is something along the lines? Not perfect and not saying this is better than yours, I'm just experimenting with somethign along the lines partial to 1970 since your rear end went that way and its really great. The lower facia of this has characteristics of 1970 in it. The lower lamps, I dont know if those really go with it, but it was to change them enough so that the lower grille fit somewhat. I did this in Paint, so its not to scale by any means.
