Originally Posted by Skiddins

My (very limited) testing so far suggests that in low grip conditions, either fit a 1.6mm top deck with all layshaft screws, or 2mm top deck with just the center post.
Once grip starts to come up you can add layshaft screws to stiffen the car, otherwise it will want to turn up it's own backside

Ran a mixture tonight at Newbury, and center post only, was good early on, but in later rounds became inconsistent. Also noticed that with just the centre post the car would have better steering up to a point, then it was like the rear would suddenly lose some of the grip mid corner and try to kick out.

Skiddins