Why change the front suspension? It is already a very descent ball joint suspesion with reliable A-arm pivots. What more did you want?
If you want better performance, get a disc brake setup from a '71-'73? corona and swap it on. Be sure to remove the residual pressure valve from the front side of the master cylinder that is used for drum brakes. Or use the '71 power booster setup.
Next, work on putting a better front sway bar & solid mount on the car along with a pair of KYB shocks. Finally, get some descent wheels with 50 series or better tires on them. The tire choice will make the largest performance improvement of anything.