Sure, slot the gears and advance away. Be sure to check valve clearance when retiming....
I was big into building 450r engines and I never once saw any gains from advancing cam timing. I alway made power either straight up or retarded. That also was a uni cam where you move one side and are forced to move the other.
Here we have two seperate cams so you can retime one without having to do the other. But I never saw added power with advancing, and I have done extensive testing with many, many camshafts.
I would have 10 or so cams in their own carriers complete. Id have my engine on a stand. Id shim each and every cam exact, degree each one straight up, and index a cam gear for each camshaft to allow for up to i think it was 5 degrees in both directions. On a dyno, Id test each cam all in one long day in all positions, along with other complimentry surounding parts.
I had different ported heads, pipes, intakes, fuels. Id spend 3 full days trying to find the best combo.