I first reinstalled all the panel structure. I know there will be an EFIS on the left hand side of the panel, and the rib is dead center. So this rib has to be modified. It has already be done and Van's doesn't object.
The first thing to do is to cut the rib down.



Here it is done.



Then some angle is adpated to the cut part. This will allow that part to be riveted to the subpanel, the exact position will be known later.



I also riveted the airvent brackets.



An finally, I installed the steps brackets under the baggage hold floor.