I still kindof don't understand but I think this is right ..
Corsairs have the two side taillight things, and inbetween is a lookalike part connecting the two (along the top) and a flat, plain part underneath.
Pintaras have the smaller part joining the two taillight sets together, and then the black indented part where the numberplate is mounted and has the illumination lamps.
From what I can gather, you basically want to change the pintara rear to be like the corsair one - plain and flat. However I gotta say, when you consider that the numberplate and illumination lamps (which will also have to be covered so they're not just omnidirectional lighting) will be jutting out from the otherwise flat surface, no offense but I reckon it wouldn't look very good at all

Either you'd have to pull off some clever tricks to make it look good, or perhaps the easier option, put a Corsair rear centre part and bumper on.