Normally a Holley WITHOUT a secondary power valve and a rear metering block will have 8-10 size bigger jets in the rears. Usually are about right that way. I wouldn't drop them down to 72's from 82's in the rear, thats too lean!
Alot of people claim this but in reality it depends on a few things as to what the jet split should be and it can vary from 1 jet size to 10 jet sizes. The power valve channel restrictors have an effect on the jet split. If your primary block has real small restrictors the split will be very little. If it has big restrictors the split can be alot. The high speed air bleed sizes also has an effect on jetting so if the air bleeds are way different on the primary and secondary sides there will be a bigger split. Then there's intake manifold fuel distribution which can even cause you to need different jet sizes on all corners to keep the mixture the same (or close) on all cylinders.
