How can I achieve the correct garden tap orientation when threading it in?
The threads are not all exactly the same. Using some Teflon tape on the threads will allow for some adjustment without leaking. Pipe threads are tapered and will seal prior to not being able to turn further. I put a few wraps on the pipe and when it starts to get stiff to turn I will leave the faucet in the proper position. (With most fittings I could go at least 1 more full turn or sometimes even 2 so it will end up in the correct position without leaking.