Shift light and gear indicator

Hello, I'm new to the Arduino and only have limited knowledge in electronics/programming. However I'm currently building a car to race and rather than buy a shift light and gear indicator, what a better way to make them as I've always had an interest in electronics and programming, just never got stuck into them but now I have a specific goal I hope I can do it.

So this is the kit I bought https://www.amazon.co.uk/gp/product/B014L11IN6/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

So the shift light, I know which ECU pin is the RPM signal on the car (although won't be able to test anything until the car is built and running). I want 4 green, 4 orange and 4 red LEDs to come on when building up to the limiter (currently 7600RPM but may change), and I haven't decided if just the 4 red LEDs or for all 12 LEDs to flash once above a certain RPM, for example 7500RPM.

The gear indicator I'm thinking just one 7 segment LCD to display which gear is currently selected, I was thinking of having 6 switches on a bracket around the gear lever. I assume the code would be fairly straight forward e.g. if switch1 is pressed then show number 1 etc and if no switch is pressed then display "n" for neutral.

Does anyone have any pointers/tutorials or any useful information etc?

If I can complete these 2 projects then my next project would be to record telemetry for example throttle position, brake position, steering angle and record engine information e.g. air temp, water temp, oil temp etc and display on an LCD.

Thanks