Numbers on those charts are not wrong, just only part of the story with the rest of the factors affecting them +/- 5 degrees. So transfer duration for peak power at 7000 rpm somewhere between 115 and 128 will work. For 8000rpm same. 9000rpm same. Getting the degrees right is one thing. Angles, crank, inlet, exhaust (port/pipe), bore, stroke, weights can all wildly change the outcome. Experience and experimentation.
Best approach is to decide where and how much max power you want and hope you have enough torque left to get there.
I think another 0.3mm on the BGM will be enough for the last try. Torque is even more important to your set up. Low gearing helps but still need the torque.
Although for the science maybe taking it up to 128 degrees after testing 126, could be good information for the record. Once the tuned MHR is on it probably won't come off.