Up all night so I did a bit of testing of wheels and tires on the Merc C9.
The above combo of Marka/PN was good but lacked a bit of steering. So I went to PN KS-M LH Wide Med, and W-PN BBS 0mm, and the steering got better. Last I kept the 1mm wide fronts and switched to 14mm PN KS-M Soft Radials on Reflex Speed Dish 0mm. And WOW did both steering and speed increase! The wide wheel/tire combo didn't do much on the 787B, compared to new KS-Ms, but greatly improved the C9! I'll run a set of laps for time later today, but I think they will be fast, for me!

Here's a few pics with the new wing and Wide Wheel Setup.