You cannot use LED bulbs in flashers. I guess you found that out. Most are not dimmable, but that never bothered me. I have the three instrument bulbs in Vixen's dash replaced with LEDs ans I really like it. Really bright and I don't give a fig that I lost the dimmer ability.
I'm with you as far as not really caring about that...just figured if there was an option out there I'd try it. Apparently you can use LED's for the flashers, you just have to use an electric flasher plug. I just watched a video explaining that.