CAD Drawing Dimension Revisions

I have a single CAD drawing file, severla pages that currently sits in PDF format. Everything about the layout, layers, and annotations is fine; the only thing that must change is the set of dimensions... (Budget: $10 - $30 AUD, Jobs: 2D Drafting, 2D Drawing, 3D CAD, AutoCAD, Building Architecture, CAD / SolidWorks, CAD Drafting Review, CAD/CAM, Drafting, PDF)