Bulk Excel Data Cleanup

I have roughly 200 pages of numerical data that need to be moved into a master Excel workbook and then cleaned up. After the transfer, a straightforward find-and-replace pass has to be run on a set of simple, case-insensitive strings I will supply; no regular expressions are necessary.

Here is the flow I have in mind:
• Transfer every dataset into the template I provide, keeping existing row and column order intact.
• Run the find-and-replace routine exactly as specified, confirming each replacement only affects the intended cells.
• Deliver the final .xlsx file plus a brief change log showing which terms were replaced and on which sheets they appeared.

Accuracy is critical because the numbers will feed into automated reports, so I will spot-check random cells before sign-off. If you are comfortable handling large-sheet operations in Excel (or Power Query/VBA, if that speeds things up) and can finish reliably within the agreed timeline, this should be very straightforward.