How clear does my wine have to be before bottling?

I started my primary fermentation with fresh, concord grapes from my parents back yard the day after Thanksgiving. We used a 5 gallon bucket, stirring daily for one week.
We transfered it to the secondary fermenter, added a bit of sugar and water, and left it there for 4 weeks. My parents basement was around 60 degrees Fahrenheit, too cold for yeast, so we moved it upstairs where it was warmer.
Since then wine has stopped bubbling and cleared up a bit, but I am afraid of bottling it too early and having a disaster on my hands. How clear should the wine be before I bottle it and how can I be certain it is finished fermenting? [I have no tools to test the specific gravity]

I forgot to mention that my parents, when putting it in to the secondary fermenter, did Not completely top it off with water. There is some air in it. [This is probably a bad thing?] Should I just top it off with water and see what happens? Will the wine be okay without being topped off? Do I no longer have wine and just some vinegar mixture??

You are ok not topping up while secoundary fermentation, But fresh grapes you will need to rack a couple more times even after it has cleared. Bottling after more like 9 mounths.