I was hoping to avoid that, but it makes sense to see what I'm up against. I'm going to swap intakes so the valve covers will need to come off, I know one bank had a bit of sludge, looked like oily dirt, and might swap heads for piece of mind too. If I'm that far I guess I'll know what's going on. And I just wanted to fire the engine and go! I'll still out some Marvel Mystery Oil or Evaporust if they carry it at the local parts store.