That depends on what cracked version and what packer the cracker used.
For the floppy Skidrow version the file LEVEL1 must be packed with the same packer the cracker used(I believe Power packer) and then put back on the disk.
This may be difficult because it is a NON-DOS disk and the files must be put on the disk at a specific place and in a specific order.
So the edited level when packed must be the same size or smaller than the original otherwise it may overwrite other files.
Unless someone wants to re-crack it and use a file loader instead of a track loader. Then there shouldn't be a problem.