One way of getting a definitive answer is to try an get an original sales brochure. I've got a 1750 Mark 1 brochure at home so I'll see if there are any useful pics in there. Also, keep an eye on adverts like this:
http://www.classicalfa.com/cars/1750...HD%201969.html
Although annoyingly it doesn't show the ashtray!! It would be worth having a go at wire wooling your ashtray. I'm sure it would come up well.