Sunderland will be backed by around 40,000 fans in the capital and there is set to be another impressive flag display to greet the players.
The Spirit of 37 tweeted: “Plans finalised and submitted. Permission granted. Order ready.
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"We now need you! Please help us find the BIGGEST fan led display Wembley has EVER seen!”
A message on there read: “The Spirit of 37 are crowdfunding to raise money to put on a display for our upcoming League One Play-Off Final.
"This is the biggest game of our season so far and we want to do as much as possible to help get the lads over the line.
“All money raised will be put towards the display. Items purchased will be used in the display on Saturday 21st May and in subsequent displays.
“Please give as much or as little as possible.”
At the time of writing, more than £2,500 had already been raised.
The Spirit of 37 are a fan-led group, whose aim is to improve the Stadium of Light atmosphere by way of displays and tifos.
They are newly formed but have been part of the flag displays at the Stadium of Light this season.