When the YJ came out, it was made at the Brampton, Ontario AMC plant initially. This was the same plant that had made CJ7s in later years. You could tell the Canadian CJs from the Toledo CJs, in that the embosed name on the lower cowl was "Joop" with the 'e's painted, out of the Canada plant. In the Toledo plant the name was stamped "Jeep." (All YJs have the "Joop" stamping)
When and whether YJ production was moved Stateside I don't know. The TJ was run out of a new plant on the grounds at Toledo.
I read that YJ is actually a true Canadian Jeep, in America its a Wrangler not a YJ. I have a Canadian model if that actually matters. The vin starts with 2.
Both my 95s are American built (Toledo) for the Canadian market (including the Canadian specific options), The registration information on Jeep YJs in Canada does indicate the model as a "WRAangler" though it's physically labeled and stickered as a YJ in the market... Jeep was not permitted to use "Wrangler" as their brand/model name in Canada as it was already owned and tradmarked by GM for a trim level in the 4x4 work trucks in 82.
1995 YJ 4.0/HO - Beef-bar, XD9000i, and still working on the lift!
1995 YJ 4-popper - once Royal Canadian Artillery enlisted, judging by badges found behind the dash.
2000 XJ 4.0 - so far only fix what breaks every other Tuesday.
My ole' Yj has all the traits of a fine lady... Everything bad that has happened was always my fault and at least once every month it refuses to warm up for no apparent reason then of course it wines incessantly from the top end for several days.