The Devils came under some early pressure as they found themselves trailing by 10 points after the Rockets provided all the first four race winners.
But Plymouth steadied themselves by having the first man home in eight of the remaining 11 races and hauled their way back in contention with an 8-1 from Ben Barker, on a tactical ride, and Sam Simota in heat ten.
Devils team manager Lee Trigger admitted: “We were pretty much dead and buried after going 12 points down following heat nine, but the 8-1 brought us back.
“We eventually took the lead, by one point, for the first time after a 5-1 from Todd Kurtz and Simota in heat 14 and we knew we just needed a race winner or, at least, to avoid a fourth place in the last heat decider.
“The game plan worked with Kyle Newman beating Stuart Robson, while Barker made sure he held third spot from Robert Branford in case anything happened to Kyle up front.”
Simota led the scoring for Plymouth with 15 (paid 17) points from his seven rides while Barker, guesting for the unavailable Jack Holder, finished with 12 (paid 13) from five.
Robson top scored for Rye House, dropping only one point from six when he was beaten in the final race.
Plymouth: Ben Barker 12+1 (5 rides), rider replacement for Stefan Nielsen, Steve Boxall 5 (5), Todd Kurtz 5 (4), Kyle Newman 9 (5). Reserves: Sam Simota 15+2 (7), Ellis Perks 2+1 (4).
Rye House: Ryan Douglas 3 (3), rider replacement for Cameron Heeps, Kasper Lykke 7+1 (5), Leigh Lanham 6+1 (5), Stuart Robson 16+1 (6). Reserves: Ben Morley 6 (5), Robert Branford 7+2 (6).