Issues with turn signals!

[E.D.75GMC]

Hello everyone, over the past couple years I've slowly been converting all the lights on my '75 GMC over to LED. It's at the point now where every single bulb has been replaced with an LED, with exception to the headlights. They've been great and really make the truck pop at night time but ever since I put LEDs in the front turn lamps I've noticed that the signal lights slow down and eventually stop flashing when you're stopped at a red light at night with the headlights on and whatnot. Now they've always slowed down a bit when coming to a stop, but I figured that was just because of the old school non-relay light system. I installed 50 Ohm resistors in parallel with the front turn lamp LEDs as the per instructions and I'm wondering if that's perhaps too much resistance? Or should I swap the mechanical flasher relay out for an electronic unit? And would adding relays for the headlights help as well? I should mention that the truck also has a 100 amp alternator and cab clearance lights (LED) wired in to the headlight switch at the dash. Any advice is appreciated, thanks!