Starting with the wrist, my rifle has the fairly common problem of unequal contact. I've packed paper shims into the gap and hope this will be sufficient as I don't really want to get into the epoxy/resin options.
I relieved (slightly too much) wood between the front and rear hand guards as they were contacting each other. I've also used a 4 thou. feeler gauge to ensure I'm not getting contact around the sight base from the front hand guard.
Now we move onto what I'm having difficulty with. The front hand guard and forend had a gap the widened in the middle between the barrel band and nose cap. I laid the hand guard on a sheet of sand paper and slid it back and forth to remove high spots and get the mating surface level. But rather than getting a nice tight fit, I've ended up with a more consistent gap down the whole length!

Everything's done up tight and it's a firm fit that doesn't move, yet still the gap! I can only think that it's fouling the harmonic barrel band thing inside the stock.