To cut the plastic in half I literally sawed and bent mine until it snapped apart, fortunately where I wanted it to snap!
The little bit of electronics screwed into the plastic section is best left there, obviously they need to be moved across with their pieces of plastic so that your speedo and tach don't become inaccurate.
After this it is all very easy, just reassemble the dash and install it back into the car. Because I've used a complete dash with the electronics for the 260kmh section, my speedo is perfectly accurate! Also because I kept the 9000rpm tach from a VR-4 I still have the AYC bars, and AYC red warning light. All of the warning lights work perfectly fine.
was the clear plastic was cut in half? what glue to rejoin the clear plastic back together? acrylic glue? no interference with optitron light i supposed?
Honestly, I don't think that bradc will answer anymore... He hasn't been online since months.
As said via PM, no need to rejoin the acrylic and there is also no effect on light spread through the acrylic.