Torsion bar mounting points- how do you know if they're ok?

My father has had his share of A-bodies including two Dusters that he loved but it has been 35 years since he has had one of his own.

Whenever I mention my interest in upgrading the suspension and tires, he reminds me that as soon as I start hammering my Dart around corners, components are going to break, likely starting with the 44 year old torsion bar mounting points. He could have a point.

My car is pretty rust free and has lived a relatively easy life but it does have 140,000+ miles on it. It's not hard to imagine that there could be fatigue in this area.

How do you guys address this before upgrading the torsion bars, etc?

Any suggestions are very welcome.