We found new method how to put new diaphragms onto floaters!
Do not use any sharp tools to avoid cuts.
Just find proper strong rope with less than 1mm diameter.
Put the new diaphragm carefully onto place, adjust direction for groove, dip the rope into oil, press exactly on the edge and go all the way around for few times. Just make sure once is done that is all the way inside (look for the membrane overall look assembly).
If someone needs more, i can send a photo how to do it exactly.
Best regards