It wouldn’t be super difficult. You can see the jig that was used for the TransAm series modification, it’s pretty darn simple.
I’m just not sure it’d be worth it. Even with a nice jig and clean control arms you’re looking at a couple hours labor, plus welding supplies. Add 2-way shipping into that and to make any money at it the price wouldn’t be all that much less than a set of tubular arms, especially adding in the cost of new bushings and ball joints since those are included in a lot of the tubular replacements.
Plus you’d no doubt get some control arms sent that were pretty rough, so then you’d have to spend more time cleaning or even make the judgment call not to work on some of them because of their condition.
Not saying it’s impossible or anything, but I won’t be setting up to do it.
