Turn Signal Blowing Fuse

Hello, everyone

I have a 1989 chevy c 1500 2/w with a 305

Keeps blowing fuse
i started buy pluging the turn signal switch and taken all the lights out
then i check for power at the flasher it is a 3 prong type there is 3 wires to it one is a blue wire that goes to the fuse box, a pruple that goes to the turn signal switch, and a black that is a ground.
i check the fues box and one side from the ign is hot, the other side that goes to the flasher is ground.
i unplug the flasher and the ground is gone in the fuse box
when i put hot wire to the purlpe wire the turn signals work but dont flash.
i got a circle flasher with 3 prongs it is a tridon stat 550 are all flashers the same as long as i have the three prong on it. please if anyone can help what i need to check. thank you

All flashers are close enough as long as they look the same and have the same number of contacts.

Check the circuit boards in the rear taillight assemblies

If you have a trailer harness, disconnect it and see if it that fixes it.

Maybe you've already got this problem fixed but I thought I'd throw in my two cents.
I was blowing turn signal fuses last summer and tried everything to track it down. Finally found that it would blow the fuse when put into reverse.(manual trans) Turned out to be a faulty reverse switch on the tranny.