deleting is not a good idea. you should comment out the lines or section, as deleting will throw out your line numbers with other advice, it is always best to comment it out and leave a note on one of the lines so you know why its commented out.

it is also wise to list in a file on your pc, what functions you have changed and their file and line number, so you can see at a glance what might be affected with upgrades in the future.