[DirtyLarry]

I have seen this on several 4.8, 5.3 and 6.0’s and they usually don’t bend valves. No need to pull the head. Loosen the rocker arm then use compressed air to air up the cylinder with a high quality compression tester adapter, which usually has a provision for an air hose. When done right, once the cylinder is filled with air you may remove the valve spring without dropping the valve down into the cylinder. If you ever replaced valve stem seals with the head on the engine before it is the same procedure.