The Sons of Struth launched a red card display against the current Ibrox directors during Saturday's 3-0 win over Ayr United and now plan to follow that up with a letter campaign.
In their statement to investors controlling around 90 per cent of the club's shares, they will ask them to "stand with the vast and overwhelming majority of the fans and demand change on the Board at Ibrox" and to also "recognise the strength of feeling amongst Rangers support about the way the club is being run".
Rangers will stage their annual general meeting on December 19, where a bitter boardroom battle will culminate.
Chairman David Somers, chief executive Graham Wallace, finance director Brian Stockbridge and non-executive director James Easdale all face a re-election vote.
But four other rebel shareholders - Paul Murray, Malcolm Murray, Scott Murdoch and Alex Wilson - will also have their bid to become directors decided upon by stakeholders.
SoS Spokesman Craig Houston said: "We're saying to the major investors: 'Don't turn your backs on the fans'.
"Working with all the organised fan groups and the response we had from the fans in the stands shows without doubt that the board as currently composed does not enjoy popular support.
"To protect their investment and for the club to flourish the investors have to stand with the fans. It's time for change."