I don't know what you would consider "easy." Since you are using a whole protein as the substrate, would it be feasible for you to follow the deacetylation reaction by measuring the change in mass of the whole protein using intact protein mass spectrometry? If you are already set up for it, this method is pretty straightforward and with the right equipment it has the mass resolution needed to see the loss of an acetyl group from a 50 kDa protein.