From memory the Ceramic Turbines are 20+ year old Garrett T28 Turbines.
N1 = Garrett -7 / Garrett -9
Garrett -9's have a marginally smaller Compressor Wheel compared to the Garrett -7.
But allow for more top end as the configuration / pitch angle of the turbine blades is different.
HKS GT-SS = Garrett -9, but with a different Turbine Housing.
Good for response and perfect for street performance.
HKS GT2530 = Garrett -5, but with a slightly bigger Compressor Wheel.
Would be "laggy" for street unless you rebuild the RB26 / 2.6lt HKS V-Cam or go for a 2.8lt / RB28 HKS V-Cam.
I got the standard VIC Roads Slimline Plates and they are 'bendies'.
You'd have to go custom slimline if you were to make them fit without bending them.