Sorry if some of this is obvious?
Tighten your quench to .035".
Reduce your initial spark lead.
Slow up and lengthen your spark advance curve.
Consider a high gear only 2-4° spark retard (45 years old, H/T Bill Jenkins)
Higher number PV.
Step up the mains 1 number.
Bigger ATF cooler.
Retard the cam 4° (watch your exhaust P-V!).

Boffin Emeritus