Hydrocodone is 5x-6x more potent than Codeine, both by the oral route. Furthermore, Codeine requires demethylation by liver enzymes to be rendered into Morphine. Hydrocodone does not rely on such a mechanism, hence it is easier for us to make estimates regarding end potency in a given individual. Different individuals possess different levels of enzyme presence/activity based on numerous variables, race being the biggest indicator, medications etc.
We can only use our best estimate, so there you are.
I won´t overload anyone with crazy mathematical theorems. Matt Damon once told me that 50 x 5 / 6 = 250mg - 300mg. That´s easy enough, the problem is, you can´t be consuming that much Paracetamol/APAP, period. Just because it is not the stated lethal dose does not make it any less harmful to your liver. That would be 2.5g-3g. You need to perform a Cold Water Extraction. It´s really easy if you focus and don´t dick around.
Take your however many pills. Crush them into a powder. Chill a glass of water in the fridge. Take your powder and mix it with the water. Put the vessel back in the fridge. Give it enough time for the sediment to drop to the bottom. I prefer using an oral syringe to pipe out the layer of cold water, leaving the sediment at the bottom. Most people use a coffee filter and decant through into another vessel. Either way, you are separating the cold water, containing a tincture of Codeine, from the sediment containing the APAP. Voila, Cold Water Extraction.
You then consume the tincture and get rid of the sediment.
For the record, 300mg Codeine = 30mg Morphine. This dosage is far below dangerous, so we shouldn´t need to worry about OP so long as he doesn´t make huge increases.