Having cut some buggerd spheres open to see what’s inside the only difference I could see is the conical alloy piece in the bottom
(I’m told some blokes like conical things in the bottom……each to his own )
Can’t remember which is which, but one is longer than the other.
Interestingly the Trophy model spheres have a different part # and use the same part front and rear……. I wouldn’t be surprised if the only difference between the normal spheres and Trophy spheres was the cones.
To remove this you’ll need to have the sphere off the car.
Apply air pressure to the fluid port, this will push the diaphragm down, once it’s all the way down ( with to pressure still applied)
Take a firm grip of the cone and twist it out of the rubber retaining ring of the diaphragm.
To fit the replacement push it into the rubber retaining ring of the diaphragm, release the air pressure, I then apply vacuum to the fluid port to make sure the rubber retaining ring of the diaphragm has a good grip of the cone.