[lxndr]

The valve stem seals are the first parts to go into the head while assembling. You'll need to take the whole head apart in order to get to them. You could also use compressed air to hold the valves in place without removing the cylinder head, but this method is a PITA! If your motor is at the age where it needs the valve seals replaced, you should also look into rebuilding the whole head while you're at it. But once you do this the restored copmression will probably blow the piston rings so you'll be looking into a complete motor rebuild (this happened to me). I'd just drive it like this until it dies. Besides if it's just bad valve seals, your motor will only blow smoke when you first start it and very faintly as you drive. If you've got huge billows of smoke, you've got bigger problems.