Hi James,
An intensely discussed topic amongst many Canadians living close to border points with the US. To be fair, our GD dealer (in Canada) was much more even-handed in discussing this topic than other RV dealers that I talked to. Some of the scare tactics used by Canadian RV dealers to dissuade customers from buying in the US are laughable. Their refusal to do warranty work on these coaches is less humorous.
To the specifics of your question . . . I can only offer what I see on my purchased-in-Canada 5th wheel. It would be interesting to put it side-by-side with a US unit to see how much difference there really is. I can't believe that GD has different bins of parts, boxes of appliances and spools of wire for Canadian vs US products.
Some of the labelling is English/French but not all of it.
Almost all of the component literature notes that these devices meet CSA standards.
I had reason to take apart an electrical outlet and noticed the CSA logo inside.
The axles have both UL and CSA on the labels.
It will take input from someone who took delivery of their GD product in the US, to know if there is any difference.
Rob