r11.5.10.2 to R12.1.2 E-Business Tax when we don't use Tax? Help?

We have a fairly vanilla system - A/R, A/P, INV.. we do not CHARGE tax via A/R  we occassionally pay tax via A/P. We're told we should not implement E-business Tax, as we can add lines to A/P invoices to pay or accrue the tax (fine by us).

we got our DEV system available to start testing and getting all kinds of errors. I found a note 811272.1 -to turn off or disable tax calculations. However, there is no data upgraded fro operating units/regimes.  

in a/p diagnostics it shows E-business tax as not installed.