Instead of cutting the wires, they make a took that will let you remove the terminal blades from the housing. You can probably get it at a parts store or order it online.
It allows you to remove the wires from the socket without cutting them, then when you are ready, slide them back into place.
Here is a link to a video I found online. The guy kinda rambles on a bit, but he demos how the tool works.
Wire removal tool video
NOTE: This is not an endorsement for the video or his link to an amazon site where he can get a kickback when you buying it from them.
Hopefully this will help you out. Nothing worse that getting a new harness, then finding that it won't go where you want it to without cutting your NEW harness.