Making the indentations isn't too difficult, i've done it successfully to create custom length cables and to turn broken ones into smaller sizes. Use a small cutting bit on a rotary tool (dremel) to cut the indentation. It helps to meanwhile mount the cable in a drill and have it rotate around slowly so you get an even cut. The indentation doesn't have to be perfect, or even down to as small diameter as the original cables for the ends to snap on. Simply cutting a semi-circle profile (as opposed to square profile as per factory) seems to work just fine.