<VV> Jetting Advice?

[Grant Young]

I have a customer with a new FC with an older rebuilt engine (but with few miles) that lives 9000' ASL. The engine is a transplanted 102 HP and he wants to replace the carbs with 1965's to get the power circuit. My question is about how lean to go with these considering the altitude and what happens when trudging up the mountains at WOT? I have always heard and read to drop a jet size from stock for each 5000', which would be .048 - .049", but the power circuit seems to add a new variable to consider since the power jet is in the .030" range and will be in use much of the time. Any suggestions based on experience or actual expertise will be greatly appreciated. 
Thanks,
The Carbmeister