I'm prepping my fuel tanks for installation. I chased the threads for the fittings and then did a test fit to make sure everything went according to plan.

Being tapered threads (NPT) I'm concerned about tapping them too deep, which would fall in the category of "bad". With that in mind all I have done so far is chase the threads to clean them up, and not made them any deeper.

The sight gauge and vent fittings don't concern me but the main fuel fitting should probably be oriented in a specific direction shouldn't it? With the finger screen and elbow in place, one of my fittings points to the rear of the aircraft. The other one comes to a stop while pointed forward and slightly up. Say, 10 O'clock if it were the right tank. I know that's not right but I'm trying to figure out how it should be oriented.

Should it point straight back, straight down, 45 degrees down/back, or what? How many threads should still be visible on the finger strainer and barbed vent fitting? My plastic fittings for the sight gauges go in quite a ways but don't bottom out, so I think I'm okay there.

Thanks in advance.