Great Britain overcame the early loss of captain Paul Sculthorpe to record a crushing victory over Tri-Nations champions New Zealand at Knowsley Road.
Great Britain: (18) 46
Tries: McGuire 2, Graham 2, Long 2, Senior, Gardner
Goals: Sculthorpe, Long 6
New Zealand: (4) 14
Tries: Vainikolo, Paleaasaesina, Fa'afili
Debutant James Graham, Danny McGuire and Sean Long all scored a try each in both halves as Britain grabbed eight in all to put down a Tri-Nations marker.
Lesley Vainikolo scored the opening try for the Kiwis but the hosts were 18-4 up by half-time and well in command.
Keith Senior and debutant wing Ade Gardner also scored after the interval.
Long landed six goals from seven attempts in a dominant display as the Lions surpassed the 38 points they put past New Zealand at Huddersfield in last year's Tri-Nations.
A lapse in concentration saw Iafeta Paleaasaesina score a second for the Kiwis with 15 minutes left, but further tries from Gardner and Long reasserted Britain's dominance.
New Zealand had the last word with a try for Warrington winger Henry Fa'afili, but the under-strength visitors were comprehensively beaten.
They started well when Stacey Jones launched a high kick in the direction of debutant Gardner in the second minute.
Vainikolo's try proved a false dawn
The Saints winger was brushed aside by Vainikolo, who collected the ball in the air to touch down.
Debutant Kiwi stand-off Ben Roberts missed the goal - and that was about as good as it got for the visitors.
Britain were level by the seventh minute as McGuire raced onto Long's pass, dummied inside Jones and weaved outside Clinton Toopi for a classy try.
Sculthorpe's conversion put his side in front, but the captain - finally leading the side for the first time after being made skipper a year ago - was cruelly forced off with knee ligament damage after 16 minutes.
Keiron Cunningham had already had another try ruled out when 20-year-old Graham entered the fray in the 25th minute.
Barely a minute later the young Saints prop showed exactly why he is so highly rated with an angled run to finish off a score created by Terry Newton.
It was a good night at the office
Newton was also at the heart of the next try, fending off three Kiwis before off-loading to the outstanding Paul Wellens, who sent Long racing through the middle from halfway.
Long converted both to give Britain a commanding 18-4 lead - and it might have been more with Gardner denied a try when Martin Gleeson's pass was adjudged marginally forward.
Britain started the second half on the defensive but kept the Kiwis out before Wellens stepped into the line to send Senior over after 47 minutes.
The full-back then sent Graham through for his second after Long's cleverly weighted chip.
When McGuire stepped between two defenders to put Britain 34-4 ahead in the 53rd minute, the game was already up.
Only Fa'afili's last-minute try prevented Britain from eclipsing their highest winning margin against New Zealand, a 53-19 victory at Pau in the 1972 World Cup.
Great Britain coach Brian Noble:
"It was just the exercise we needed. That gives us a lot of confidence.
"We've got a pretty good team there, and that's as fluent as we've been with the ball.
"Defensively we were very, very strong. That was a good New Zealand team. To keep them to 14 points is really pleasing.
"We saw some shape and good tries from our guys as well. It was a good night at the office and gives fuel to the fire for the Tri-Nations.
"It will also fuel New Zealand's fire at the end of the year. If they watch this down under they'll be thinking 'yes, Britain can play a bit'."
New Zealand coach Brian McClennan:
"It was very hard for us, we only had two training sessions.
"It shows that Test football is very difficult and you have got to have that familiarity with your team-mates.
"But it gives players the opportunity to play. We really don't get enough Tests.
"The Tri-Nations is a great concept but other than that we don't get a lot of international football.
"Anything that helps rugby league has to be good."
Great Britain: P Wellens (St Helens), A Gardner (St Helens), M Gleeson (Warrington), K Senior (Leeds), L Pryce (St Helens), D McGuire (Leeds), S Long (St Helens); S Fielden (Wigan), K Cunningham (St Helens), A Morley (Sydney Roosters), J Peacock (Leeds), G Ellis (Leeds), P Sculthorpe (St Helens, capt).
Replacements: T Newton (Bradford), S O'Loughlin (Wigan), L Gilmour (St Helens), J Graham (St Helens).
New Zealand: C Toopi (New Zealand Warriors), L Vainikolo (Bradford), S Hape (Bradford), W Talau (St Helens), H Fa'afili (Warrington), B Roberts (Canterbury), S Jones (Catalans, capt); A Chan (Catalans), M Tony (Hull), I Paleaasaesina (Wigan), A Lauitiiti (Leeds), D Solomona (Wakefield), D Kidwell (Melbourne).
Replacements: R Paul (Huddersfield), H Hansen (Wigan), V Anderson (St Helens), M Betham (Wakefield).
Referee: S Clark (Australia).