thanks for doing all the 'leg work', as Mike touched on all is OK with the terminal vent to atmosphere if you have an alternative main stand.
I've found using this routing and terminating anywhere in that general area results in an oily rear stand for those of us that use them.
My present setup vents about 2" beyond top left hand corner of the licence plate, which gives acceptable result but looks ugly and no doubt in due course will be rubbed against by the unwary.
The best / tidiest method IMO, is that shown in Richardson's (?) with metal vent tubes running along the pillion footplate / lower LHS frame member of FT6/2AS ? and directed down and away.