I remember taking my 85' 626 into have a new ball joint put in.
The mechanic had the portable press to push the new oversized ball joint in, right on the car.
But he had the part off kilter when he pressed it in then it just fell out after removing the press/clamp, so he decided to to gas weld it in.
The thing was glowing red hot and all the grease and plastic bushings came boiling out of the top of the brand new ball joint.
Then, sure as s*** the welds eventually broke. I took it somewhere else where they welded it with an arc welder but kept spraying it with water after every tack so as not to cook my next new ball joint.
They weren't exactly supposed to weld that kind of thing so my invoice just said "miscellaneous labor" and they wouldn't warranty their work.
A whole new LCA would have been easier and better but I didn't know any better at the time.
PS... Why didn't Mazda just have the ball joint just bolt on to the LCA like so many other cars. Press-in ball joints are just stupid.