Rich Barcelo, one of the overnight co-leaders, only managed a 2-under 70 in the fifth round and is alone in second place at minus-16.
John Merrick (67), Cameron Beckman (69) and the other fourth-round co-leader, Michael Boyd (71) are tied for third place at 15-under-par 345.
Any player in the top 30 -- including ties -- after Monday's final round will receive a PGA TOUR card for next season. The following 50 will earn full privileges on the Nationwide Tour.
Golfers rotate over the Stadium Course at PGA West and the Jack Nicklaus Tournament Course. There is no cut as all players play each course three times in this 108-hole marathon.
McNeill started on the back nine Sunday at the Jack Nicklaus Tournament Course and parred his first three holes. He birdied the 13th and 16th holes, but did most of his damage on the second nine.
He parred his first four holes on the front nine, then knocked his approach to 4 feet at the fifth. McNeill holed the birdie putt to get to 16 under par for the championship.
At the par-5 seventh, McNeill hit his second over the green, but chipped his third from behind the putting surface inside a foot from the hole. He tapped in the birdie putt, then played a strong tee shot to 10 feet to set up birdie at the par-3 17th.
McNeill did struggle getting into the clubhouse and the reason was somewhat humorous. He walked past his caddy at the exact same time as his caddy was putting away his putter the club smacked McNeill in the forearm. McNeill admitted that he had trouble feeling his arm on the ninth tee.
It showed as his tee ball landed in the first fairway. McNeill played a strong approach, but two-putted for his par and his share of the fifth-round lead at Q-school.
'I've had the same mindset since June when I started to practice again,' acknowledged McNeill, who led after rounds of Q-school four years ago, but did not get his PGA TOUR card. 'The mindset is don't get ahead of yourself. I'm here to win, not breeze by.'
Paul Gow (68), Darron Stiles (69) and Robert Garrigus (70) are knotted in sixth place at 14-under-par 346.
Anders Hansen (66) and Bob Heintz (69) are tied for ninth place at minus-13.
Currently, the cut line for players to earn their PGA TOUR cards is 8-under-par 352 with 33 golfers making it.