601-XLB - 600 hrs - top rudder hinge rivets loose. Noticed a bit of play lately - barely noticeable by pushing up on the bottom of the rudder at the tip. I thought it was a bit of wear at the hinge bolt. It seemed much worse today. Just took a closer look and the rivets holding the top hinge to the rudder are loose - noticeable movement between the two.  Red X - Code 3 - Grounded.

So now the rudder needs to come off - I think.  Wondering if I can replace the rivets without removing it.  Do it one at a time by turning the rudder to either side.  I am looking for advice to check for rivet hole wear.  How do I know if I need to go up to the next size rivets?

Assuming it needs to come off, I am looking for advice on the rudder cables - I assume I need to loosen the turnbuckles and take the pressure off first.  Then for reassembly I will need to re-tension - what are people using for cable tension meters?  My A&P does it in condition inspections but he is not around.