Re: Where to find sheathing?
If you mean wire harness tape, then there are 2 types typically found in the trunk, the first being the typical non-adhesive wrap found all over the vehicle the wiring;
I'm sure you can find it cheaper if you look, this is for your reference.
And the other type being similar to "gaffers tape" which has a gritty feel to it as it is a tougher adhesive backed tape that was used in areas where the factory was concerned about damage from chaffing--like rear side marker lamp feeds on some cars where a suitcase or tool might try to snag them.
-If you don't stand for something, you'll fall for anything.