Wallace is very unlikely to reach second place in either the popular vote (where he was almost thirty points behind both Nixon and Humphrey) or the electoral. If Wallace had won *every* state where he got at least 25% of the vote in OTL (including FL where he finished twelve points behind Nixon) he would still have only 91 electoral votes.
https://en.wikipedia.org/wiki/United_States_presidential_election,_1968 For Nixon to get less than 91 electoral votes would require a near-collapse. And if Nixon somehow collapses, not all of his votes are going to Wallace by any means. Enough would go to Humphrey to almost assure Humphrey an electoral vote majority. To have Wallace win--or even get into second place in a no-electoral-majority election--you need a simultaneous collapse of both Nixon and Humphrey, which seems improbable.