It may not be possible to quilt such a large quilt on a small machine. I would take your quilt to a long arm quilter to have it professionally quilted. You put to much work into piecing your quilt to have it ruined by improper quilting. I do not have a longarm machine, I don't think I would be very good at it.
With the price of the Long arm machine I can have my quilts professionally quilted. I say don't stress over quilting it yourself, take it and have it quilted by a professional. you will be pleased with the results.