Guys guys, there may be a lot of knowledge out there but I think LFF is trying to tell you that his mods do not use groundbreaking methods, but are methodologies for various sound modification possibly commonly found in books. Whether a modder picks up the idea and uses it, is key. Tuning them by ear would be trial and error, and that is essentially what you need and should do to achieve your goal.
No one said modding the T50RP was going to be a walk in the park. Put some effort into it! Any modder has the right to conceal his own methods, and we need not push the case further.
P.S. concepts used for loudspeakers and headphones can be used alike. Some just require common sense (i.e. no you will not wear your headphones on cinder blocks, so no it doesn't apply <-- yes I wanted to try putting concrete in the cups, lets just say don't do it) and tweaks to get optimal results for different enclosure material, shape, and size.