The roller is centered over the valve stem ( top to bottom ) But not front of engine to back.

Take a look at #8 intake rocker you can see the keepers on one side. Not centered.

Dumb question
 

You sure this isn`t from previous damage?

Yes, was thinking maybe the bottom of the stud had some movement and not the top. I've found is useful over the years to try and look at the whole picture rather than just a portion of it. How many times have you looked at something until your eyes crossed and couldn't find the issue. Walked away for five minutes and just happened to glance at something else and the issue was glaring at you all along? I know I have many times.

I'm curious about the way number 6 exhaust rocker, roller tip is sitting on the valve.

it might just be the camera angle. But even if it isn't there isn't much that can be done since the push rods are almost hitting the intake runner. If memory serves me I had to do a bit of grinding to get the clearance that I have. I would have to move the rocker stud over to get the rocker centered on the valve stem. I will go out and take a close up look at it.

Good luck

tink,dart makes an adjustable guide plate that would help your alignment,check them out.

I cut & tig weld the guide plates to where I want them, and they should be. I don't trust the nut & cap screw that comes with the adjustable guide plates. I have yet to see a BBC that the guide plates didn't need some or alot of adjustment.

they work,i have not had any of them come loose or move.i used to cut&weld before dart came out with these.i have found that the gm plates are the best fit out of all the non adjuatable ones.