Just keep in mind that the computer will assume the base timing is set at whatever the chip sees and wont limit the extra advance through the RPM range (as well as max advance limit). So by giving it another 2 or 4 initial, your actually giving it 2 or 4 more throughout its entire RPM band. I imagine you already know this but I thought I'd mention it just incase . . .
Glad to hear all is well.
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