base amount for tax calculation in sap billing

Dear Experts,

We have a situation where out sap invoice final amount is not matching customer PO, because of rounding in SAP.

EG:

Selling Price: 74,766.36

Tax: 5,233.65

Final Amount: 80,000.01

Whereas the final amount should have been 80,000

So initially we added DIFF condition to adjust Tax amount, but it was affecting Output VAT report showing all these DIFF values

Business does not want that, so we are adding DIFF condition to net value. Now the net value and tax are as below

Net 74,766.35

Tax 5,233.65

When it comes to accounting entries are as below

01 8000485 customer 80,000.00 THB

50 2100100 Revenue Gds - Dom 74,766.36- THB

50 2623600 Output Tax 5,233.65- THB

40 2100100 Revenue Gds - Dom 0.01 THB

And the base amount considered for tax calculation is as below

G/L Tax amount Base amnt Tx Tax ra

262XXXX 5,233.65- 74,766.36- O7 7.000

Is it possible to adjust the base amount for tax calculation to 74,766.35 instead of 74,766.36?

How can I achieve it? Does it help me if I put tax condition at header level?

Please advise.

Regards

Pradeep