Not difficult to recable the L3000 at all. Remove the earpads, screws (4 screws holding the earcups and another 3 holding the driver assembly in place), and you should get to the driver. I suggest a high quality silver cable to enhance the resolution, open up the soundstage, and tighten up the bass impact. I recabled my old pair with Moon SIlver Dragon Gen 1 but this was probably around 7 - 8 years ago before I sold it to a local friend. I recently recabled my 3000ANV with the left over SIlver Dragon and the work was not difficult at all. If you are handy with soldering iron, it can be done ..... just take your time and be careful. Take pictures before and after removing the driver holder assembly...you want to line up everything the same way. Here are some pics of my W3000ANV that I recabled last week. The internals are more or less the same as the W2002 & L3000. You can do it.
While at it, get them reterminate with a 4.4 mm balanced connector. The L3000 isn't that difficult to drive and many top end DAPs of today can do wonder with these headphones. Plus, they do sound considerably better driving from a a balanced amp. They sounded spectacular out of my Balanced Gilmore Reference amp at that time.