Well, in theory it can be done..
It's kinda of a matter if the rest of the electrics can
But you'll need several things as well..
I suggest you go for LED turn signals and taillight as well as they LED's take much less power (Watts) from the system and I suppose that just changing the taillight to LED will give you the rest you need!
Parts you'll need:
-Some cable lengths with at least two different colors and some terminal connectors
-Terminal crimp
-Light switch with turn signal button and horn!
-1 diode with two input and one output
-LED turn signals
-LED taillight (make sure it's an E-approved)
-LED flasher relay
-Some non conductive electrical duct tape: to put al the wiring together
And if you're extra careful you can add an inline fuse!
You can either tap into the existing loom preferably or make a direct connection to the battery in this case I do suggest using a fuse just to be on the safe side!
One more thing.. here in Portugal you need a working speedo and "dashboard" for the indicator lights (Max and medium beam and minimum if you got it, and turn signal indicator light) and a horn!
Plus, front and rear brakes both have to turn the brake light on!
If ya need help sourcing out the parts let us know!
Vando