Update for anyone who might find this in the future or @nepbug who said he was following-
Turns out Miller sells an adapter toggle switch that is intended for later model Millers, but works on most 175's depending on the age. Part No n890025...
Thanks @PAToyota I should have clarified. I am aware of the SGA-100, but it is a standalone spool gun driver. It costs ~$400. The Miller spool gun also costs about $400, so $800 total.
For $900 I can buy a new Hobart 190 WITH spoolgun included. Doesn't make sense to spend almost as much as a new...
I have a large structural aluminum project coming up that I don’t think I want to use my tig on due to speed. I have a trusty Miller 175 mig which should push enough amperage for what I need to do but the 175’s were not intended for a spool gun. I have found some spotty evidence of folks...