Must be my day. Sorry man, but LED stuff is too modern for here. https://www.jalopyjournal.com/forum/threads/the-h-a-m-b-rules-guidelines.44274/
Welcome to the HAMB from Illinois. There are many turn signal wiring threads here that you can find with the search tool, magnifying gl*** red banner above. Regarding LED bulbs in the turn signal circuit, it appears to be something best left to the OEM engineers. The best advice for back yard mechanics is to use incandescent bulbs as they are very easy to get working satisfactorily.
What can we help with? I did the swap on my Fairlane, and the bulbs are obviously much brighter than stock ones, but I cannot get the damn things to flash on their own any longer. I thought I had the problem beat at one point by adding the inline resistors, but I guess it’s still to low of a draw to engage the flasher.
@Malp*** , if you want the old bulbs to look brighter, paint everything behind the red lens, except the bulb socket, with gloss white. Painting a couple coats with a 1/2" brush makes it easy.