Also think about the other end of the car; see
here. Be careful and skeptical about "LED bulbs" sold to replace filament types; almost all of them are useless and unsafe (that includes all of them sold for headlamps). For smaller lamps there are a few good ones;
these work well in brake/tail lights and
these work well in back-up lights; you will need to install
this new flasher (2-prong like original; connect its ground wire conveniently).