I was a bit confused by "Aimpoint Line" myself but I assume you mean the secondary reference line (OB edge to A/B/C on Stans system) and not the ghost ball or shot line.
Before I discuss my approach, I want to be sure we have identified an understanding of "vision center" which has nothing to do with the CTE alignments themselves.
Set a CB and OB on the table a few diamonds apart, stand behind the shot and while in the upright position, line up as if you are going to shoot a half-ball hit. You are mentally drawing a line from the center of the CB to an outside edge of the OB. When you find the exact position for your eyes where this line looks "ON", you have found your vision center. If you'd like you can wiggle your head back and forth using PJ's half-the-distance formula to extrapolate your way to the center.
I want to point out "vision center" because the physical alignment can vary from person to person. We are lining up two eyeballs on one line that changes the convergence between our eyes the farther the line extends away from our face. 3D aficionados might call that a parallax view. So, depending on the given shot, your shot perception, eye dominance, etc. find what looks right to YOU.
Now we have identified "vision center", what I do with CTE is first find my "vision center" on the CTEL, then if necessary, I make a slight adjustment to the "vision center" of the secondary line. This is where I stop, and I believe this is the position that PJ is asking for in his poll.
This is how I do it and it works for me regardless of which system I'm implementing. I don't think this is how Stan teaches his system, and it would be best to ask him directly if you are specifically talking about CTE/Pro1.
Of course from this position, I then focus on the face of the cue ball, move my head/eyes straight in on the CB and slide the cue stick into a 1/2 ball (or 1/2 tip with pro1 CTE) offset, then pivot to center CB.