I received the replacement step rib #4 so I could continue with the step ribs of the right wing.
A while ago when I was setting the rivets of the right step ribs I made a mistake. The rivet in the corner is difficult to set correct and I elongated the hole when drilling the rivet out.
Next I filled the elongated hole with JB Weld and after 24 hours I reamed the hole from 4.1 mm to 4.9 mm.
The rib was de-burred and primed with wash primer.
For the backside I made a doubler.
The 10 mm rivets that TAF supplied are on the short side for the in total 5.3 mm thick parts. I used 13 mm long rivets for the 4 mm rivets and 15 mm long rivets for the 4.8 mm rivet (for the elongated hole):