mig welding a steel reducer sleeve into cast spindle

i have decided to use uni balls on my upper rear arms on my supra irs. I drilled out the upper ball joint hole to 3/4". I then got a reducer to drop the hole from 3/4 to 9/16. There is a minimal amount of movement of this sleeve in the hole i drilled. Is this something to concern myself with or could (should) i weld this sleeve in place. would there be any problems. I wouldnt think so since it doesn't appear to be a structural point on the spindle....just needs to keep the sleeve in place. But le tme know if my thinking is off

I'm not max, clearly, but in my opinion if you do decide to weld it, which is an interesting process it will need to be structural.  The slop that you have currently can easily wear down the inside of the spindle and eventually cause major issues.  Sleeving the spindle should be a press fit or as close to as possible.  I had one sleeve that once drilled I could push in with my fingers, it wouldn't move but easily pressed in.  I welded beads along the outside of the sleeve and ground it back down in order to get the tight fit that I wanted, perhaps you could do the same depending on how much slop you have currently.

thats what i was thinking....grinding a slight taper on the top edge of the hole i drilled and welding and grinding smooth with the top of the spindle....i also though of drilling a hole, tapping it and inserting  set screw or not tap it and weld a pin in it