Triumph_Custom_Tune_list. 3 & 4 Cyl. models also has custom tunes that have been uploaded by people. You could conceivably start with one that approximates your changes and then fine tune on a dyno. Really, all custom maps are just approximations, as all engines are a little different.
Get a laptop, a TuneECU cable from
Lonelec and the free TuneECU software and that can be used to tweak the maps. But of course you need someone who knows how to dyno tune/tweak appropriately, too. The tools are just part of it.