hoyt carbon defiant info. Where do you guys place the level on the riser?

Looking to start from the beginning again this spring. I've had my carbon defiant turbo for a few years now. I've always struggled feeling confident on selecting a spot on my riser to call the bow level. Like if I want to establish my center shot again and set my 3 axis points. Do you guys use the riser, or the string?
I tried putting a string on the center of my top and bottom limb bolts and establishing a center shot that way. I feel like I've got a solid nock point set up. But the string I set up on the limb bolts are to far right compared to how my strings and cams line up.
I've had trouble with paper and bare shafts tuning last year, I took it to a shop and we spent a long time just getting it close but I never liked the bare shafts flight past 20yds. To me that screams center shot issues if my bare shafts are hitting my target at an angle?
My bow did shoot my fixed blades good out to 80 last year however. Able to keep moa groups.
Thanks for your time.

With the Defiant series I always put the bottom of the arrow at the top of the rubber shelf/protector that covers the berger hole.

For center shot I measure 13/16" off the riser and not the rubber shelf.

What cam# is your bow? The #2 cam bows had an issue with vertical nock travel that might be your issue as well.

Got ya. I have a #3 cam set up..