I've got an old Astro Power Powermig 130 I want to use as a flux-core welder. When trying to use it the other day, it was welding horribly, so I did a little research and found the welder appears to be wired for DC electrode positive polarity, while the wire I'm using requires DC electrode negative. There are a few flux core wires out there that run DC+, but the ones I have seen are pretty specialized and not usefull for everyday/all position welding.

I want to just swap the ground (38) and electrode (51) wires around, but the problem I'm running into is the switch to turn on the feed control (30) gets its signal at A1 from the lead going to the electrode (51). This means that if I switch the ground and electrode wires, the current going through the switch and A1 is also going to reverse direction. So I was thinking I need to rewire the welder as seen in the lower diagram. The only problem I can see with this is that the wire going to the A1 terminal of the feed control (30) is now on the opposite side of the transformer (32) as it was before. Do you think this will cause problems?

If this can't be done the only other options I could come up with is to install a microswitch in the stinger which would then be separate of the electrode power. Or get a new stinger with a switch already built in. Or don't even mess with it.