Shut off timer or fader for LED's......

[myclone]

While your idea seems simple at first glance its actually going to be kind of complicated to do in reality with analog electronics. Do do what you want and have it turn out decent is going to either take some programming and a PIC or a big clunky circuit board with 555 timers (or similar), gates, etc.

To fade an LED array slowly is the simple part but then you have to take into account the quick movement of the shifter from P to D or any other selection which could be faster than the display would dim the last selection then light the next. For the analog system to work youd need multiple inputs and circuitry to, for example, "immediately restart newly selected gear indicator fade with any gear selector movement and cancel previous indicator selection/fade". It could be done but yeeesh it would be a nightmare in analog.

My suggestion would be to seek out some "tinkerer" type electronics engineers (maybe we have some on this forum?) who would find it interesting/fun to do some simple coding to be able to use a microcontroller like a PIC to do what you want and using such a device would simplify things greatly.

There are sites with DIY electronic circuits/ideas out there that may help you but be prepared to apply some basic electronic theory and knowledge to use them. Simply put if you dont know what the resistor color code is or ohms law then you may quickly become frustrated and abandon the project. Bowdens hobby circuits is one such place and there are several other electronic sites linked from it with even more ideas should you have the time/desire to slog through all of them.

Probably not what you wanted to hear but if you decide to check out the bowden site you may at least get a few ideas or what have you.