Finding Values from one Column and replacing equivalent row in seperate column

Here is the setup:

In Column A, I have a list of thousands of part numbers which each have a specific part number.
In Column C, I have a column which I desire to be filled with military part numbers (This is not specifically populated yet for all entries in Column A).

In Column Z, I have a specifically filtered down list of a few hundred part numbers. These part numbers all match a part number in Column A (But these are not in equivalent rows).
In Column AC, I have the specific filtered down military part numbers that are associated with the part numbers in equivalent rows in Column Z.

What I desire to do is Find part numbers from Column Z, search for them in Column A. When it comes across the same part number in Column A, I want it to replace the same row of Column C with the same row that it matched up with from Column Z in Column AC.

Ex.

What I have now:
Row# Column A Column C Column Z Column AC
25 100-10-8 (blank) 111-10-8 M25/12
50 111-10-8 (blank)

And I desire:
Row# Column A Column C Column Z Column AC
25 100-10-8 (blank) 111-10-8 M25/12
50 111-10-8 M25/12

This is the case for several hundred part numbers, which would be annoying to find and replace them all.

Any assistance is appreciated.
Thank you,
Marc

In C2, if you wish ONLY the military part number to appear if it exists for the matching value in A2, try this formula:

=IFERROR(VLOOKUP($A2, $Z:$AC, 4, 0), "")


If you want C2 to show the AC value when it matches or the original A2 value when it does not, then:

=IFERROR(VLOOKUP($A2, $Z:$AC, 4, 0), $A2)