The flaps are mounted using piano hinges and there are two ways in which the pins can be configured to mount the flaps. The first is to run the pin from the inboard end all the way through to the outboard end. Drill a hole in the steel aileron and push the pin in there. The problem is that the flap pin is very difficult to push through all those eye holes while holding the flap at the same time.
Option 2 is to remove two of the eyelets in the middle of the hinge and split the pins. It makes it easier for the pins to be fitted and removed if need be. The pins need to be cut, bent and chamferred at the ends so they fit more easily. the bent ends locate in the middle of the flap. To fix the pins in place I drilled three holes in the flap brace for a number 6 screw and nutplate and rivets too.
It was a surprising amount of work to get the flap pins done today but at least their done.
After that I mounted the right flap by riveting the second half of the piano hinge to the wing structure and fitting the hinge pins which worked a treat.