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5ma seems enough to me, they don't have to light up like an airport runway, but even at 10ma, they need to be independent, so just make 6 parallel circuits of LED, switch, resistor.

LED resistors are simple to figure. Start with your power - 9v. The data sheet says 2.7v forward drop on the LED. SO in our circuit, to get 2.7v across the LED, we need to drop 6.3v across the resistor. Ohm's LAw tells us that when 10ma flows through a resistor and 6.3v drops, then the resistor has 630 ohms resistance. 680 is a common standard value close to that.

If you had all six lit, you'd draw 60ma from the battery. If you wanted more than one LED to light up together, you could series them and use the same 10ma through both, but you want them all independent, so you can't series them. SO six LEDs, six resistors, six switches.

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