He has made two changes from the semi-final clash, Thomas Pascoe coming in for Dragons centre Jack Dixon and wing Luke Morgan getting his first opportunity since the opening game.
Wilson said, "Thomas played well against Samoa, and made a good impact in areas when he came on against New Zealand on Sunday. He deserves another chance to start, plus Jack has played a lot of rugby for a very young player.
"Eli (Walker) has played well on the wing but Luke deserves his chance. He has trained well during this tournament and played well for us in the Six Nations. We have had no choice other than to keep the majority of the side together for almost the whole tournament as they have played so well with three great wins. The front row in particular has been the cornerstone of our performances with the set-piece possession they have provided, and Kirby (Myhill) has led the side well in Cory Hill's absence through illness.
"Our big focus now is on getting this win tomorrow and finishing third in the world. We've only had one loss so far in the tournament, to the defending champions, and we want it to stay that way. It's not going to be easy though, Argentina are an immensely committed side and it's going to take a top performance to beat them. They have already beaten France and Australia and got to the semis. They have a good scrum and line-out, and a very quick back three.
"We won't change our game massively. We will need dominance up front which will be tough because Argentina are a very physical side but we also want to get our back line going when we can.
"We believe the players have enough left in the tank. They are battered and bruised but also very motivated to go home with the tag of the third best team in the world."
IRB Junior World Championship third place play-off - Wales v Argentina - Friday 22 June 3.30pm UK time (live on Sky Sports 2), Newlands Stadium, Cape Town
Ross Jones (Ospreys); Tom Prydie (Dragons), Cory Allen (Blues), Thomas Pascoe (Blues), Luke Morgan (Ospreys); Matthew Morgan (Ospreys), Tom Habberfield (Ospreys); Rob Evans (Scarlets), Kirby Myhill (capt, Scarlets), Samson Lee (Scarlets), Rhodri Hughes (Ospreys), Matthew Screech (Blues), Luke Hamilton (Blues), Ellis Jenkins (Blues), Dan Baker (Ospreys)
Replacements: Darran Harris (Blues), Gareth Thomas (Carmarthen Quins), WillGriff John (Blues), Ieuan Jones (Dragons), Daniel Thomas (Scarlets), Jonathan Evans (Dragons), Owen Williams (Scarlets), Iolo Evans (Scarlets)