Turn signals don't work on 92 Chevy Silverado?

[Rob]

Ok when I first got the truck the back turn signals and brake lights didnt work at all, so i bought new circuit boards and back lights for both sides and then my right side front and back was perfect, but my whole left side was still blinking fast. So i figured it had to be my front left bulbs, but when i replaced the front flashers and running lights for the front on both sides, it made the right side all blink fast and the left side not work at all again, also when i went to change the fuse after this, the dash flashers quit working and now nothing blinks at all on the outside. I have no idea what else it could be, would the turn signal switch cause this? I know something could be grounded bad or pinched but i couldnt find anything that was?