Work to execute the plan. Take the first steps

As part of the continuing segment on Managing Opportunities or Problem Areas....

If you have agreement on a plan or can execute the initial steps yourself or within your group, do so. Any actions taken should not be irrevocable, but initiative toward solving the problem shows your bias for appropriate action. Both employees and managers outside your group and senior management will recognize that you are willing to put your time and energy into solving problems for the customer and the company.

Operate outside your circle of influence, objectively and customer-based and company-based. When the good of the customer and company are the lens through which your story, plan and execution are based, the arguments are lessened or melt away.