hey Ant good result i was just looking at your setup and see you ran 2.5 deg rear toe-in at the rear and was wondering if you tried 2 or have ever ran 2 deg at the rear?
Racing in the UK on asphalt I often start at 3 deg and end up the day on 2 as the grip comes up and find I can lap so much faster.
I run on a sprayed asphalt track, very tacky. in 17.5 boosted I usually run 2 degrees but sometimes Ill even run 1.5 depending on the conditions. It all depends on the track layout and class also.