That site just estimates. Not everyone the same height has the same size legs and arms.
I have a 4th gen but I can say the lust lowering triangles are nice. All except it makes putting the bike up on the centerstand way harder.
Yes. Car oil has friction inhibiters that will eventually make your clutch slip. So yes, there is a difference and why I said not to use it.
Don't use car oil. Bad for the clutch but you can use Rotella T6 or something like it for diesel engines if you want to save a little money.
My back wouldn't be able to take it but that is a beautiful bike!
Separate names with a comma.