So I had Renthal bars and apex stem and the grid on the bars lined up with marks on the stem. The middle marks on the bar lined up with the middle mark on the stem.

Now when it comes to lining bars up on my standard stem any idea how the grid lines up?

stupid question from a stupid rider lol

Simply measure the bars to find the centre then cut a line with a hacksaw on the centre to mark it.

Simple!

Haha! What I meant was how do I know when they are at the right angle as the grid is on the top of the bars not at the front like most bars.

Dremel in some horizontal marks perpendicular to the hacksaw mark..?

If you clamp it hard enough the faceplate will leave marks you can use as reference.

Drill a big hole in the top of your stem so you can see the marks.

One wishes to have never asked.

Sit on the bike, pull the front brake, bounce up and down a bit. Are you happy with the bar position? Yes = tighten the clamp. No = tweak and repeat.