For me, regulator came off, new brass parts went on. The regulator was screwed onto the knob/valve assembly but was removable with a pair of wrenches. Not welded on - just screwed. You should be left with a male threaded 1/8" connection (what went into the regulator). Just noticed on my amazon links, make sure you get the right sized parts.
For me that was 1/8" to 1/8" female/female coupler, then 1/8" male to 1/4" female adapter, then 1/4" quick disconnect.
