Having owned both models (a 2018 Gold Wing, and now a 2020 Gold Wing Tour), I can tell you definitively that they are in fact different dashes, or what the parts catalog calls the "meter". The tour has more features like TPMS pressure display, options for electronic adjustable rear preload, traction control, etc., all of which require special lights and LCD segments. The part # for the Gold Wing meter:
METER (MPH/KPH)
37130-MKC-A11 37130-MKC-A12
The part # for the Gold Wing Tour meter:
METER (MPH/KPH)
37130-MKC-A01 37130-MKC-A02
I should mention that I pulled these from the DCT models. The standard transmission models might have another part altogether. I didn't check.
Oh, did I mention that these meters are $3,500?
So if you were wondering why I traded for a 2020, now you have a better idea. And all I wanted was the bloody trunk and TPMS. My bike's traction control has NEVER kicked in, and I set the rear preload once and never touch it again. In fact, the non-tour has a wider adjustment range for the rear preload, even if it is a bit more inconvenient to adjust.
The long and short of it is that it doesn't make financial sense to try to turn one model into another. There are aftermarket TPMS solutions (which are better), and like I said I've never even had my traction control kick in on my bike (that I know of at least), and there are certainly options for trunks. Your money would be better spent on getting a Traxxion suspension setup on the base than doing anything else. Just my $0.02.