As a general rule the left side is the hot side. But by no means is this a "Rule". It can be either side as electricity does not care...
Get a 12 volt test lamp, pull the fuse, using the lamp touch the terminal where you just pulled the fuse. One will light it up and the other will not. The lit side is the hot side.
If you want straight power, goto the hot side. If you want it fused, go to the cold side. Once the fuse is reinstalled you wire then would have power that is fused..