A 15W40 would probably work well for you but the T6 should be fine also.
I have run the T6 5W40 several times in my ST1100 with 8,000 mile OCIs and the UOA results have been very good. The ST is a shared sump water-cooled V4.
The typical SUS vis at 210F was 65.9 for the T6, 66.0 for Mobil...