Brighter dash lights..?

Earlier this week I asked for opinions on getting brighter dash / gauge lights.
A lot of good feedback, mostly recommendations for LED's. I installed several different brands and they all seem to greatly improve the brightness...but, none of them worked without some issue, like not being dimmable or causing blinker lights to stay on...one set of LED"s looked great but had a constant flickering. Is there something that needs to be added or done to get the LED's to function properly..?