4 Speed Pedal Rebuild Went South - Help!

I completely missed that- geez I'm stupid.
This welder may not be the greatest thing, on/off, feed, and min/max, I had it at min of course- doh!
Max is 80 amps, is that hot enough for this?

Live and learn, I like doing things myself, but that damn spring needs to come off and on again- anyone have any input on that monster?