Foreign Tax Credit on Cap Gains for dual citizen?

[neoplop]

I am a dual Citizen (US/Canada) residing in Canada.
When I moved to Canada, the ACB of stocks for Canada was set by the deemed acquisition upon entering Canada. The ACB for the US remained unchanged.
The stocks are now held in Canada.
I assume the "Saving Clause" (Article 29, Paragraph 2) of the US/Canada tax Treaty makes any gain from the sale of the stocks taxable in the US. (Without the Saving Clause , they would be taxable in Canada under Article 13, paragraph 4.)
Is it incorrect to assume that the gain should also be declared in Canada?

Assuming the sale of a stock is declared on BOTH US and Canadian returns:
The ACB for the US and for Canada will be different, as will be the Cap Gain Tax, especially since only 50% of the gain will be taxed on the Canadian side.

How does one reconcile this with the Foreign Tax Credit on Cap Gain? I am assuming I file for a credit on the US side with Form 1116, since the gain arises out of Canada. Is this correct? Or should I be excluding the gain on one side or another under treaty terms? Canada does not think of this gain as foreign income and therefore does not allow a Foreign Tax Credit for US tax paid of the gain.

When filing US Form 1116, how does one determine the amount of Foreign [Canadian] Tax paid on a stock sale when the gain for Canadian tax may be vastly different from the gain for US Tax?

My instinct says to subtract the cap gain from the Canadian return to obtain a tax liability "without gain". The difference between this recalculated tax liability and the actual tax liability would be the Canadian tax paid on the gain. But this seems convoluted...

My head is spinning. Thanks.