Australia-born duo Lachlan Coote and Jackson Hastings are set to start for Great Britain in the tourists' opening match against Tonga on Saturday.
Head coach Wayne Bennett gave a clear indication of his line-up for the game in Hamilton when he announced a 21-man squad, omitting Jake Trueman, Joe Philbin and Blake Austin from his full touring party.
Coote (St Helens) and Hastings (Salford), who both qualify through an English grandparent, are lined up to start at full-back and scrum-half respectively, while Wigan's Zak Hardaker is set to start at centre.
Hardaker, who was a late call-up, is a specialist full-back but his last appearance for England was a centre and he looks set to get the nod ahead of Jake Connor.
Former St Helens forward James Graham will join one of rugby league's most exclusive clubs when he leads out the Lions at the Waikato Stadium.
The 34-year-old St George Illawarra prop will become only the fourth British player in the history of the game to win a half-century of caps, following in the footsteps of Jim Sullivan, Mick Sullivan and Adrian Morley.
The match has been given official Test match status and so Graham is set to become the eighth recipient overall of a Golden Cap, awarded by the Rugby League International Federation in recognition of his half-century.
The squad announcement was delayed after the Great Britain squad were evacuated from their Auckland base because of a major a fire at the neighbouring SkyCity Convention Centre.
The centre of Auckland was covered by smoke from the fire and the team have been moved to Hamilton a day earlier than planned to prepare for Saturday's game.
The players, who had been on a day off on Tuesday, left Auckland at 5pm local time to make the 69-mile trip south to Hamilton.
Smoke can be seen billowing through the air and doesn't seem to be slowing down. Our reporter on the scene @aneksmith says the surrounding streets have been shut down. 🔗: https://t.co/5WIMbsLGhD pic.twitter.com/2myQOqXIX0 — RNZ (@radionz) October 22, 2019
A spokesman said: "It all happened very quickly. Within an hour of being told to pack their bags we were on the coach out of Auckland."
The team were due to train in Auckland on Wednesday before making the trip but will now train in Hamilton instead.
The 24-man squad and support staff flew into Auckland from Sydney on Monday after attending the inaugural World Cup Nines tournament last weekend to embark on the first Lions tour to New Zealand since 1996.
The Great Britain banner was mothballed in 2007 to enable the home nations to compete separately but the Rugby Football League bowed to pressure to bring it back.
England coach Wayne Bennett is in charge of the Lions, who will open their four-match tour against the Tongans at the 25,800-capacity Waikato Stadium and play two Tests against the Kiwis before moving on to Port Moresby to face Papua New Guinea.
GB squad: L Coote (St Helens), J McGillvary (Huddersfield), Z Hardaker (Wigan),
O Gildart (Wigan), R Hall (Sydney Roosters), G Widdop (St George Illawarra), J Hastings (Salford), C Hill (Warrington), J Hodgson (Canberra), L Thompson (St Helens), J Bateman (Wigan), E Whitehead (Canberra), J Graham (St George Illawarra, capt), J Jones (Salford),T Burgess (South Sydney), J Lomax (St Helens), A Walmsley (St Helens), J Connor (Hull FC), J Hughes (Warrington), G Williams (Wigan), D Clark (Warrington).
