I've seen guys in car toppers on the Nik around the golf course area (where they park the boats) do well. I've only ever fished from shore with a fly
and that's not easy with the dyke. Spoons and spinners seem to be the most effective. Very frustrating river... I could never nail down a bite aside from
first light.
A longer rod helps, as does using the steeple cast. If possible don't cast directly back at the dyke. In many places on the river a cast of 30 feet or less is all you need. Coho will often hold right against the bank so casts directly downstream or up are possible when fish hold against the near bank.
As far as fly versus spinner etc. No doubt spinners and spoons are effective. However I often carry 2 rods, fly & spinning and sometimes I will have a coho chase a spinner to my feet, refuse it on a following cast or two but take a fly immediately once I switch.