See the gold foil label in post #40 above. It would be a long shot to find an original 'Delta' foil wheel label that has survived over 45 years but there is one out there somewhere. I saw it on eBay and asked the seller for a copy and measurements but received no reply from him in Italy.
I have Delta Milano center caps, although some of mine are reproduction caps, which I understand from Osso, are available through facebook Alfa groups.
Yes, I have been in contact with this 'wheel collector' each year for the last four years. He wants to keep this wheel worse than I want it. Besides his wheel is missing the original Delta wheel foil decal anyway.
Thanks to Bellagt (Ken) for reminding me of this thread. One of the original prototype Montreal wheels was sold, in a lot of 3 oddball wheels, when Bertone's assets were liquidated at auction. If anyone knows where the Montreal wheel went, I am interested in it.