Some valve lifter noise is typical of the 3.2/3.5 engines. The problem can be resolved by replacing the complete rocker assemblies with later design ones - cost a few hundred dollars - I’m thinking something like $250 per side. There are some past threads with all the info., and perhaps someone more knowledgeable on the subject will post. That particular design issue won’t lead to failure.
There is also an eventual catastrophic failure scenario that can occur on the rocker assys. due to the main rocker assembly rod rotating and blocking off oil flow. Again, there are past discussions about that, and maybe someone who knows more than I do will come along and help with info.