First of all we need to know what dose the patches are. If you are able to take 180mg of morphine then you have a good tolerance profile to take fentanyl, but make no mistake, it will still make you OD with relative ease. Fentanyl and morphine are entirely different beasts. To start, DO NOT take more than the equivalent of 25mcg/hr patch. That's approximately equivalent to your morphine dose, but fentanyl can be rather unpredictable sometimes, so seriously no more than that before you get comfortable, and avoid redosing. Also keep in mind using fentanyl will increase your tolerance at an unprecedented rate and if you do that long enough, it's likely you will never enjoy the opiates you're used to again. Plus, I like to describe fentanyl as 'the crack of opioids', since this is the only opioid that has really made me fiend, ever (or 'morish' as is now popular). The duration is so short that you will want to redose every 30-60min. Even hydromorph I could hold for days w/o issue, but if I had 3 100mcg/hr patches for 3 days, I'd be through half by morning, and down to half a patch by lunch. I also find it actually keeps me awake rather than nod, which is a fucking bitch tbh.
Anyways what you ask is correct, swallowing would be pretty much the worst thing you can do. While chewing the patch, you need to keep the saliva on the inside of your cheek (buccally) or under your tongue (sublingually) for the fastest onset. If you think that patches are designed to be absorbed through your skin, the only thing you really want to avoid is swallowing it and destroying the fent in your GI tract.
Now as for extraction for IV, this is really walking the thin line of harm reduction but I'll say this, placing the fentanyl in an acidic solution will result in the conversion to a form that is soluble in water. Even weaker acids like ascorbic acid (vitamin C) or acetic acid (vinegar) will work just fine. Just make sure if you do follow this route to follow the dosing I have stated and to dilute the acidic solution unless you want to set your veins on fire.