The Election is tossed to the House, and Wallace plays kingmaker and makes Rockefeller President, but has himself Vice President.
This couldn't happen. In the event of no majority in the electoral college, the House picks among the top three candidates for President and the Senate picks between the top two for vice president. Since Wallace didn't get any electoral votes as a vice presidential candidate the Senate couldn't even consider him in the first place, doubly so considering his ticket wouldn't even be in the top two.
In addition, in OTL Humphrey and Nixon made a deal that if the election went to the house they would both pledge to support the winner of the popular vote. I wouldn't be suprised if something would have happened like that here.