Help with 1959 Dodge Sweptline front suspension upgrade/conversion ideas?

Do you mean Styleline? Swepties didn't start until '61...
Check out the front suspensions from F/M/J cars, have been popular with rodders for years- just unbolt the K frame and out comes the whole front end, all self-contained. Transverse torsion bar suspension, disc brakes, power steering. Bolt/weld it in and go (well, sort of). Plus it stays all Mopar, and you can get parts for it anywhere.