boxer/ignition/knock sensing question

[baldy]

Hi all, i will soon be in the process of fitting five exhaust bungs to my alfa 1.7 16v alfa sprint, 4 of which will be to check the idle mixture of each cylinder on the down pipes and the fifth for higher rpm jetting of the carbs downstream of this this will use the wideband lm1.I have also fitted megajolt programable ignition ecu with great results over stock dizzy. my question is what is the best/safe way of setting ignition timing above 3000 rpm? it is currently set to alfas own manual specs.but i beleive it could be tweaked cheers lee