I would advise against altering magnet system. You will end up having to alter other things & possibly damage diaphragm in process. Planar magnets are very strong. Neodymium magnet normally have a nickel like coating on them but a not so well healed manufacturer could have left them uncoated in which case the could look like ceramic magnets. These magnets if left uncoated will deteriorate over time as Neodymium is sensitive to exposure to atmosphere though it may take years for it to become a problem. There are many different strengths of Neodymium magnets as well strongest being I believe n52. Some Neodymium magnets are not much stronger than sammarium cobalt which is still stronger than ceramic or alnico magnets.

Also separating the diaphragm from front housing to get at front magnets if present can cause diaphragm to be torn if glue is overly strong. There is usually screws holding it together but also a small amount of glue that may have got on diaphragm face that needs to be separated to get to front magnets. If you make magnet polarity mistake on assembly or allow magnet poles to shift even slightly on reassembly the magnet system can go from full repell to full attract causing the magnets to slam into each other damaging the diaphragm in between.

Magnets have to be setup to repell when assembled. All North poles facing each other as well as south poles doing the same if there is magnets front & back of diaphragm. As you look at the side of magnet facing the diaphragm the poles facing the diaphragm go in a north-south-north configuation though bear in mind some manufactueres face the poles to the side instead of facing diaphragm. A method of alignment is needed to prevent shifting as magnet assembly is being pressed together. It is nearly impossible to do by hand as the difference of having magnets repell or slamm together is only the gap between the magnets on either side. 1/8" side shift is all it takes to have magnets slamming into each other.