6 volt positive ground signal light question

[benbuilder]

I think i need some help. I am going backwards. I feel so stupid. I should know better.
6 volt positive ground truck.
I started to install signal lights in the car.
I have a double pole switch to go left/off/right. This is installed.
I installed two rear 6 volt lights to be used as signal lights.
I did not install the fronts yet.
I have a fuse at the battery. Fuse was removed.
I ran the positive lead from the signal lights to the switch.
I grounded the base of the signal lights to a good ground.
I was going to test my work so far.
I had the feed to the signal switch in my had and was going to ground it or i did ground it, i dont know. But the second i installed the fuse it burned out. I quickly removed it.
I disconnected all my work and installed a fuse. I have power on one side of the fuse but not on the other.
i have tried 3 fuses.
Any thoughts on getting power back?
I can worry about the signal lights after