Rod: With mild steal to mild steal all most any rod rated (Good) will do for this type of gob. Find a you like and stick with it.
To cast: The 70s likes cast. But many will do just fine.
Amps: Penetration, penetration penetration. What ever amps it takes to cut deep. Many people not use to rod end up running cold and just ends up laying it on top, It looks good and is easy to grind off after the weld false.