I noticed that the left side of the deck was not raising and found the left lift arm broke where the adjustable linkage attaches (number 15) in the exploded view. The adjustable linkage part number 7 was bent. All of the parts are part of the tractor warranty and the dealer ordered them on an emergency basis so I would get them the next morning (today).
I picked up my service manual during my trip to the dealer for these parts. When I go home I looked in the manual and it gave the steps to remove the lift arm, which looks pretty easy even without the manual. No such luck. Both left and right lift arms were rusted on would not simply slide off the rockshaft which they are keyed onto. What I did not notice in the manual was it says to remove the floor board for better access. Both lift arms are on the keyed rockshaft for a distance of about 3 inches so penetrating oil takes some time to work its way through. It took a pry bar and a long punch to finally get the lift arms off (45 minutes or so). I cleaned up the rockshaft ends with emery paper so the lift arms slide on and off easier. It will go back together with a coating of long term grease of some type.
The linkage view was difficult to find on the parts breakdown even for the dealer parts man. Go to the alphabetical listing and look under "mower lift linkage"