pb84,
Congratulations. Very well done. I had a Canadian IR (now lapsed), which I acquired in my mid-40s. Even though I had had previous instrument experience, including a PFIG in a UAS, I found it the most intellectually difficult exercise I had ever undertaken, including physics at university.
I did mine in a 172 and it was clear that the standards and expectations of both my instructor and examiner were exactly the same as if I had been doing it in a Boeing - "4200' please, not 4220'". My examiner was an ex-CF104 pilot and although he was slightly bored by the pedestrian performance, he was very keen to make sure I was able to meet the standards. One of his techniques was to engage me in conversation to see if I could still keep up with my situational awareness.