Why can't you find another ash tray and take it apart, modify it to hold your tach? Great idea, I think I might do that very same thing. Thanks for the Idea.
I would but the GT silver dash front is unique to the GT models only. I really dont want to hack up an ashtray made of unobtanium. However I have decided to go the traditional route and just mount it to the steering column. I think theft of these isnt as big as it was back in the earlier days.