This has no impact on whether or not you need an 07 or not. 01 is the correct license for custom rifle building on other peoples guns. Building or modifying guns for resale with any modification like changing stocks or sights including bluing or paint is manufacturing and requires an 07 license and ITAR registration. This is regulated by BATF and ITAR.
ITAR registration has their own definition of manufacturing and it doesn't matter what BATF license you hold. If you meet ITAR manufacturing registration requirements you must pay the fee, keep track of guns modified under this regulation and pay the taxes. You do not need to get an 07 unless BATF changes their requirements.
Since I build no guns for resale (not even one) according to the way it reads is my 01 is fine for working on other peoples guns but any activity that require drilling, milling, threading, changing caliber, capacity or any modification for accuracy including bedding requires ITAR registration, records and possible additional taxes.
I'm certain this will kill the guys that do it on the side for themselves and friends because doing it for profit isn't a consideration. The way it reads that anyone modifying even one gun is in the business of manufacturing and doing it without registration is punishable by no less than one year in prison. That means at least $2250 ITAR registration to thread your own barrel for a muzzle brake or hang a barrel.
If Hillary wins this is just the start of more regulations that will eliminate our freedoms. Like him or not, Trump must win this one.