I need a structural engineer

We want to remove the (Fink) roof trusses in our house and put in a cathedral ceiling. Existing trusses are made of 2x4. Total length is 24 feet across. Height is 53 inches. Approximately 13 feet on each side from the outer wall to the peak. So basically it's a triangle of 13x13x24. I have a plan for what I'd like but want to confirm viability with a structural engineer.