Be aware that these 3-4 bearing methods are time intensive. They work as long as you don't get spotted. And who knows, later in development convoys might change course when you don't expect it. Invalidating the work done. It's better to have something crude than have nothing at all. But without visual contact these bearing-methods are all you have.
Visual perception of AOB is recommended. I hated it myself in the beginning being a sucker for precision. But over the years learned to embrace it. Because it is the quickest and (with certain error) the most sure way to know what it actually is. Hazard to take a guess when looking at it, it costs nothing. And when you match it with information gathered later on you'll get beter at it. Specific angles can be quite accurate to perceive if you look at the details. (0, 90, 180) Start with a crude perception of AOB, then use that to move to a better position to ascertain those precise ones. All the while checking if all your estimations/measurements still hold up to the current state of affairs. (To stay with the Easter mindset
) Don't put all your eggs in one basket.
For another visual 'bearing' method you might want to consider the following thread in the SH3 section. It is based on historical logs and actual German doctrine:
https://www.subsim.com/radioroom/sho...d.php?t=222377