Ford 6.0L Power Stroke Diesel :: How To Diagnose And Replace A Bent Push Rod

I had an huge amount of work done to my 2004 Excursion (early model 6.0) earlier this year. ARP studs, new HPOP, ICP, IPR, Ford lifters, Ford push rods, EGR delete, Bulletproof remote oil cooler and filter, EBP sensor and tube, Ford head gaskets, and a bunch of other stuff including eventually a new FICM (not Ford) and a new 140 Amp alternator.

My problem is it sounds to me like some sort of metallic tapping is going on and it doesn't feel as smooth as I would expect -- like a very soft miss. Currently the tech says that there are no "low contributing cylinders". I am wondering if there may be a slightly bent push rod? He is adamant that a bent push rod won't stay where it is supposed to -- I say it depends on how bent it is. I am also worried that a rocker arm may be bent or deformed in some way.

My question is this; Once the valve covers come off -- if nothing looks wildly wrong, where do I begin to confirm that I do not have bent push rods or damaged rocker arms? He says that in order to check the push rods we would have to remove head bolts off of the rocker arms (I think I have that right). But he said we run the risk of compromising the head gaskets if we touch anything like that. If we have to remove head bolts (stud nuts for me?) can you take one rocker arm loose, check that rocker arm and push rod, and put it back together safely? Without having to pull it all the way down and put new head gaskets, etc? That would mean releasing the clamping pressure across both heads at each rocker arm -- is that creating the potential for blown head gaskets?

I know in my youth we would roll push rods on a sheet of glass (12" X 12") because glass is supposed to be flat -- can't bend it or deform it without breaking it first. I assume that still works. I now have a Scan Gauge II but it is not set up yet to check all of the readings for the sensors. I also believe I need to check for leaks with simple green and to make sure I don't have any exhaust leaks. But what about the push rod/rocker arm question? Is there another way to verify integrity?