Matching 2 files in Excel

I have 2 sets of 4 Excel sheets with large amount of data. 2 raw files and 2 processed files. I have done a mistake in the processed files and replaced 2 separate words (Disc, Drums) to Caliper. Now I want to undo this change but the problem is the processed file has a lot of changes and modification and I can't do it by simple find and replace. I need some one to somehow match processed file with the raw file and change the word "Caliper" back to the Disc, Drums. There are supporting columns with unique data so an expert can easily do it by taking help from other columns Files will be supplied to selective freelancers because I can't upload them publicly.