I cut a 22mm hole in the center of the lid and then a long slot so I could drop it over the 22mm pipe between the back plate of the patch and the mouting bracket. I then cut a slot in the actual container to accomodate the Tx feeder and used a cable tie to secure the remaining flap to the tx feeder to secure the cover whiich just clipped on to the lid as normal.
BTW - other suppliers are available but not tested!
Enjoy both the flapjack and the container

73
Noel
PS sorry about the uncorrected iphone sideways pictures
