4000 Inboard End Boom - Gnav Gooseneck (retrofitable) SEL_509-081-09

You will need to rivet (6 no. 4.8mm dia 12mm long rivets required) this on your old boom both on the top with the three holed stainless steel plate and on he side walls. You will also be advised to bolt through to the whole seciton using the related 100mm countersunk M5 machine screw ( see related items). I would put a nut/washer at the base of the unit and the base of the boom.