Husband has hepatitis c and is experiencing 102 fever and severe body aches. We can't get the fever to go down

That's a high fever. If it were me I'd go to the ER. But that's me. This decision is up to your husband. No one can decide for you.

Since Tylenol can cause further damage to an already compromised liver, your options for getting the fever down are limited to mechanical (cold packs, cool bathwater, etc.), aspirin, or prescription medications. A trip to the doctor might also help determine the cause of the fever, which is the urgent need from what you've written.