My Evo comes with a cast steel lower control arm and i am wary of cutting the factory ball joint hole off to weld some screw in sleeves for the chrylser K772 style ball joints.  I have access to a great welder but i do not know if i would get away with welding a wrap around support to the sleeve or not.

While the later Evo ball joints will press in, they go in from the top of the hole in the control arm and their connection to the upright is not taper and castle nut like mine.

Thinking about it, it would not be hard to make a jig using a stock lower control arm (i want to retain the stock footprint bushings).  I do not want to add any adjustibility to it as far as caster or a movable ball joint for camber.  Keeping it simple as pie.  I am not aiming to drop weight or anything fancy, just to adjust the roll center.

 We don't have access to DOM tubing here on the rock but i could get it brought in (which could get pricey).

If ERW is applicable what diameter and wall thickness should i be looking for?  If not, it sucks to be me.

This is the picture i had in mind