I am also not a 2.6 liter guy, so I can't give you any firsthand advice on the valve adjustment, but I will send you the relevant adjustment information from the 1983 service manual when I get a chance. By the way - I think the timing chains on the 2.6 liter cars need regular adjustments and/or replacement and it is not a simple task.
Also, if you intend to keep the car I advise you to buy a set of 1983 factory service manuals for the K car (not the Chiltons' version- the ones the Chrysler dealer uses). Go to Ebay and wait for an inexpensive set to come up. Even if you don't work on the car yourself - you can have it to give to your local mechanic to use for reference.
Best Regards,
Ron