Yes extract it then replace it with the patched version. Then you need to push the "trucha" button in WiiScrubber then push "scrub". It'll give you 5 new files and directions on how to use them.
1. Extract "main.dol," apply the patch and replace it.
2. Click the "Trucha" button.
3. Click the "Scrub" button.
4. There should be 5 new files in the same directory as your ISO file. These are the same files that the "instructions splash," is talking about. Follow the instructions:
4-a. Replace "fst.bin" with "FakeFST.bin."
4-b. Close WiiScrubber, restart the program, and reload your ISO.
4-c. Replace "boot.bin" with "ReplacementBoot.bin."
4-d. Replace "fst.bin" with "SCRUBBEDFST.bin."
4-e. Replace "SCRUBP1.DAT" with "SCRUBP1.DAT."
4-f. Replace "SCRUBP4.DAT" with "SCRUBP4.DAT."
5. burn your ISO file to disc.
Note that for softmods you need at least IOS53 and your system menu IOS (IOS30 for 3.0-3.3, IOS50 for 3.4, IOS60 for 4.0-4.1, or IOS70 for 4.2) from cIOScorp 3.5 as the Dop-IOS ones don't seem to work.