Hello t3man,
While it's entirely possible that you are suffering residual side effects people forget that for a group typically in their 40s 50s 60s there are lots of other medical things that happen.
What I would suggest is seeing a doctor and NOT telling them about your HepC and Treatment so as to force them to consider other causes, just like they would for any other patient arriving with the same symptoms.
At 6 months the drugs are totally out of your system, as in down to the last molecule gone.
Pretty much every enzyme system, blood cell, and lots of other cells has been totally replaced by newly manufactured versions, so there are a very limited number of ways that something caused by the medications could continue. That's not zero ways, but it is a very limited number of ways.
As well as routine bloods like FBC, LFTs, Cr U&E you want things like TFTs, BSL, RhF, ANA, ESR, B12, VitD, Iron Studies to rule out lots of the common suspects.