I kept the incandescent lights in my turn signals...but did put a Sylvania LED brake/tail bulb in. As much for safety as for the clean cut-off, bright-brake to dimmer-tail. There's fewer worries about a taillight failure at night and then getting run down on the road before noticing it.
I have a couple of LED turn bulbs, but unless the housing is just-so, they're not as visible as incandescent. So I passed...
I'm assuming the flasher is hard-wired to a canbus or other un-reachable part of the electron magic web. In which case, it's easy to have a dummy load under the seat or anywhere - just splice in a couple of bulbs to the circuit. If you're only going LED on the tail, you shouldn't need more than one - and you can bury the dummy bulb behind the rear taillight housing, under the load platform.
If the flasher is available for access, and is adaptable to a standard auto flasher, just an LED or heavy-duty auto flasher should do the trick.
