How do I tune for heads/cam?

To date all that I have had to do to get things right was to tinker with the IFR table to get my LTFT's negative, so that I could get my wot AFR right.

No a new set of heads will definately change the volumetric efficency of the engine, so it seems that I may have to tinker with the main VE table. How much do a set of heads change an engine's volumetric efficency by? Could I calculate the difference in airflow between the stock to aftermarket heads and then change the VE table by that ammount? Or could I use the volumetric efficency pid and do some logging after the install and see about how much of a difference the heads make and then apply that difference to the ve table?

Right now the values in the VE table are very close to what I log, they are usually withing .3 of eachother. What is the best way to tune for a set of heads?