Extended arm positioning/slingshot holding hand

Hopefully I am not repeating a post. I did a search but did not find anything. I have been shooting a few months so I am in the process of determining what works best for me in terms of body part positioning. As far as feet position I am most comfortable with a slightly open stance. But here is the thing that I keep playing with. The position of the lead arm, or one that extends. (this is for non butterfly) Here is the base of the question:

When I am shooting and testing out "where the ammo goes" I try out different reference points on my face. Corner of mouth, or knuckle on cheekbone for example, something I can feel. When I use the mouth corner, I always seem to shoot a bit high. When I use the cheekbone, the accuracy is better, but I need to raise the elevation of my extended arm to get everything more level. Almost at eye level, which I think Fowler maybe said..."don't do that you will knock your eye out!" :>)

1. Is it better to always keep your extended arm/slingshot at the same position (shoulder level for example) and adjust the reference point on your face.

2. Adjust the level of the extended arm and keep the same reference point on the face.

3. Combination or who knows :>)

I think I lean towards raising the elevation up some as since I am older, my neck is a little stiffer, which makes it hard to tilt my head down to the bands if that makes sense.

I am probably overthinking this, and I probably will end up with what works for me, but I just wanted to check in before I build up any known bad habits.

thanks again in advance.