On receipt of permit to compute the tax on TTB Form 5110.51, the revenue agent shall:
If the revenue agent determines any variation between his gauge and the quantity of spirits described on Form 5110.51, he shall amend and initial the data in part I of the form. The revenue agent shall deliver all copies of Form 5110.51 and any accompanying package gauge record to the proprietor. The proprietor shall then compute and enter the amount of tax on all copies of Form 5110.51.
27 C.F.R. § 26.79
Approved by the Office of Management and Budget under control number 1512-0250