906 head capabilities?

New valves and pushrods aren’t going to solve the valve to piston clearance issue.
To have the in/ex clearance numbers be that far lopsided, it’s likely the cam is installed way retarded.

I would double and triple check the cam installed C/L.

If it’s indeed correct, the easiest way to get more clearance is to run a cam with less duration.

Don’t take this the wrong way…….. but you’re in a bit over your head at this point.
The P/V clearances should have been verified before the heads ever got bolted down.

Measure the valve overall lengths and see if they are close to what I posted previously.